Figuring out trends in housing, construction and property

How do you solve a problem like the ONS construction statistics?

Brian Green

You don’t need a map, satnav or signposts to drive a car from one place you know to another you don’t. But it helps. A guide is handy. It supports better choices. It saves time.

So, too, can good industry statistics. You don’t need them. But a good set of numbers can help to scale your market and provide hints at where it’s heading. Even fairly ropey stats and indicators help.

This brings me to the latest ONS release of the construction output data. These are bedrock figures for scaling the size of the industry. No other short-term indicator seeks to value the actual amount of construction work done each month in Britain.

But there are problems that need fixing and I believe the industry and its representatives should rally to press for a lasting solution to a number of problems that beset the series, those that are known and those that are latent.

These data are hugely important. Sadly their importance is greatly undervalued. Furthermore they have received growing criticism in recent years as a result of major revisions and findings that were seen as at odds with other industry indicators. They have lost the status of national statistics.

For example, a blunt reading of the latest data would say that in April the ONS decided that on an annualised constant price basis the industry was £3.7 billion bigger than it was thought a month earlier. Blimey.

In some ways this actually relieved pressure on the ONS, because the result brought the data more in line with what the industry and analysts expected, whatever the true figure might be. But this is not the first big revision. The construction output series is seen as troubled.

Revisions to construction output that in one go shift annual GDP estimates will raise eyebrows and potentially annoyance, not least when the bragging rights among some economists seem to rest on the slightest tweak in the economic numbers.

Inevitably this all undermines trust and value in the eyes of users and potential users. Sure, no statistical series is perfect and some of the criticisms of construction output data have been petty. But the scale of revisions, including the most recent, have been large. So concern is justified.

But ill-informed criticism based simply on the facts above would be inappropriate, misguided and dangerous. Many of the revisions have resulted from improvements to what is still a young data series that is bedding in.

Wagging fingers of blame and simply casting ONS and its construction data team as the villains here would be unhelpful, with unintended consequences potentially leading to a worse long-term outcome.

The industry should instead press for investment in the data series – a short-term boost to fund a deep analysis of its frailties and find long-term solutions. This I suspect would payback handsomely long term in better data and a better understanding of how to measure construction within the UK.

The alternative could easily be problems emerging periodically with quick fixes applied. That would steadily devalue the data and drain confidence. This could well lead to a retreat in its use and a consequent retreat in the coverage ONS offers in response, leaving the industry to rely increasingly on the partial light cast by trade indicators, useful though they are. Meanwhile, forecasts would have unsteady foundations on which to build a realistic view of future prospects. Our understanding of the industry would be diluted.

It’s worth reflecting on the challenge for ONS. It is relatively easy to set up a trade indicator to provide a reasonable gauge of sentiment and movement in the level of activity in a selected part of construction. I could, so it must be easy.

I couldn’t measure the size of construction output on a monthly basis. It’s a whole different order of task. Construction is an extraordinarily muddled mix of businesses, business interactions, outputs, odd seasonal effects and timeframes. Add to this the potential confusion of how land plays in the mix. It’s highly volatile and the muddled mix is in constant flux, morphing in odd ways. What’s more, simply defining construction is a task in itself.

So hats off to anyone who can measure on a monthly basis exactly how big this industry is.

This was the task ONS took on a few years ago and subsequently produced a new output series starting in 2010, which links to the previous series.

When the ONS took on the role I suspect the complexity of the challenge was underestimated, as would be the case with most people unaware of the idiosyncrasies of the construction industry. It has hit problems on the way and has had to deal with them.

The current set of revisions, which I stress are interim, relate to the output price indices. These provide the deflators used to adjust for inflation so the volume of work over time can be gauged.

Briefly, these inflation rates naturally vary between the various sectors and vary regionally. The previous approach to this has become increasingly unreliable over time. So the ONS needed a new approach. (You should read the background to all this on the ONS website.)

It has put together a temporary fix. This is far from perfect, as ONS recognises.

Those who have read the detail may have spotted that they are based on inflation rates in labour, materials and plant. But what of margins?

The reality is that changes in margins within such a muddled industry as construction are hard to measure. But you might fairly assume they shrink (even go negative) during a recession and expand when things pick up. Yes, the construction industry really does pay its clients for the privilege of working for them during a recession.

So there’s a fair chance that margins are expanding. If they are expanding faster than the other elements (labour, materials, plant) then the deflator will understate inflation in the system. This will lead to an inflated figure for construction activity in constant prices.

So basically the temporary fix has flaws.

The problem is not made easier by the lack of clarity over how the value of the margin appears within the various payments made throughout the life of a long contract and more importantly how this is express within the forms contractors fill in and send to ONS.

Is the overall margin proportionately allocated for each month? If not then how? Also, how do the amounts submitted by contractors monthly account for large and uncertain final settlements left to the end of a project?

Even if there is a neat way to solve this problem (if it is a problem), or to accommodate it, there are a host of other known unknowns. And probably plenty of unknown unknowns.

Consider seasonal adjustment. We pretty much know it is unbalanced across the year, seemingly leading to overstatement in the summer adjusted figures and understatement in the winter. Adjust for this and the growth rate in the latest two quarters may well be higher. But what procedures can you use to improve the seasonal adjustment which are statistically robust and within the protocols that determine good practice?

Furthermore we really don’t know on a month-by-month basis what is actually measured. What I mean is that some firms put in figures for work done that is chargeable, others state the sum invoiced, others point to orders received and some put in data for turnover or income paid in the month. What’s more this leads to a lag between when the work was done and when the work was reported.

This blend of different things measured with different lags will vary month to month.

And, then, we have the problem of what is actually being measured and what comes into the definition of construction. Not all construction is recorded. Construction done by firms that are not construction firms, retailers, manufacturers, charities, non-construction engineering firms would not be measured.

So, in theory, if a non-construction organisation takes construction work in house it disappears from measured construction output, popping up elsewhere in the national accounts.

These are just a few of the major challenges that need to be tackled. They alone represent a major investment in time.

So I think the industry needs to decide how much it values the construction data.

Personally I suspect it needs the data more than it recognises. In that case the industry should refrain from pointing the finger of blame and instead lobby hard for a root-and-branch review of the construction output data. This would require a well-resourced deep examination from the perspective of statistical measurement.

Among its tasks would be to review such basic things as exactly what the construction industry is, how factor inputs vary, how it does business and how this is changing, what administrative and other data it collects and in what form, how efficiently and effectively suitable data might be collected, what factors influence these data and how. The list could go on.

The key would be to build knowledge that would lead to a greater understanding of the industry and a more robust way of measuring it. From this should flow a long-term solutions.

The alternative is carping and criticising. But to what end?

Just how fast is the construction industry growing?

Brian Green

This is a question that’s puzzling plenty of experts in the field at the moment.

The trade surveys suggest strong and continued growth. The official data suggests a slowdown recently. So let’s look at the muddle of data.

The Construction Products Association earlier this week released the latest Construction Trade Survey, which pulls together a range of survey data from material suppliers, contractors, subcontractors and small builders. Its headline said activity had increased for eight straight quarters. Most of the charts it uses point to growth, with the odd exception such as contractors’ public housing orders.

The latest monthly Markit-CIPS survey showed growth, but a slowdown in growth. The meaning is hard to ascertain as the survey has a habit of being a bit over optimistic. But a reasonable take is that it suggests we’ve hit a slight soggy patch in a generally upward path.

One indicator that probably gets less attention than it deserves is the Bank of England Agents’ Scores. These suggest that, as of March, the level of construction activity was up reasonably on a year earlier, but that growth was slower than in last autumn, suggesting a similar pattern to the Markit-CIPS survey.

The first quarter 2015 construction survey from RICS, the surveyors’ body, also suggested a slight slowdown in the rate of growth after a peak last autumn. But the rate of growth suggested by its survey remains historically high. We see a similar pattern with the survey from RIBA, the architects’ body, with the exception that its monthly measure recorded a sharp rise in March.

In terms of construction as a whole, the RICS and RIBA samples are skewed to professionals working in consultancy. Therefore this is more representative of work ahead of that which happens on the ground. So you’d be ill advised to think these data track directly with construction output. The surveys are, however, very useful in the mix. The latest ones suggest future growth and confidence among construction clients, particularly for larger new-build work.

Then there’s the official measure of construction output from ONS. This has been causing a bit of consternation as it seems to be suggesting that the industry has dipped into a technical recession. We’ll see on Friday, but early estimates for the GDP figures suggest construction output in the UK was down 2.2% quarter-on-quarter at the end of 2014 and a further 1.6% down at the start of 2015.

This leaves output in 2015 Q1 almost 1% down on output in 2014 Q1. Hence the consternation.

Now there are some issues with the data. The ONS is working on improving the deflators (the adjustments for inflation) where there are tricky problems. But working out how they might impact on the adjusted output is far from straightforward. There are problems with lags in the data. This means that what we see in the March figures may well be influenced by elements of December, January and February activity depending on how firms fill out their returns.

If you look, you’ll see that the seasonal adjustments appear to be a bit out. This is a new series (starting in 2010) and it takes time to bed down. We know this. You can’t get around it. But observation suggests the data for the summer months are a bit up and the winter a bit down on what you might expect. Crudely readjusting for this (I’m not suggesting you do, other than mentally) might roughly halve the drop we see in the latest two quarterly figures.

So a more accurate reading of the output survey data might be that the industry has been pretty flat over the past year or so.

One point I have mentioned before is that the ONS data measure work from the construction sector as it is defined. There’s plenty of construction work undertaken outside of the sector, such as in-house work by companies and other organisations. So, if over the past year, say, housing associations decided to build for themselves and not engage contractors, the ONS data ought to show a decline even if the same amount of construction work overall was being done.

I use the example of housing associations because there has been talk of such a switch being made. There is no hard evidence that I am aware of to suggest how big a shift this might be, if at all. But these are major clients of repair and maintenance work, so taking this work in house would reduce measured construction output.

Organisations taking work in house would not however alter GDP overall, as the work would be picked up elsewhere in other sectors.

All of the above is either public knowledge or you can work it out from looking closely at the figures. And ONS is addressing those issues it can.

Jobs graphs 14 05 15In mid-week we received the construction employment figures for the first quarter. These add yet another set of indicators to the pile. And opposite I have cast some graphs from the data.

What’s worth noting (not charted opposite) is that the message from these data is that the number of people working in construction is growing slower than across the economy as a whole.

Despite the talk within the industry of rapidly rising workloads, the number of people estimated to be working in construction in the first quarter of this year was just 1.5% up on a year ago. That compares with employment growth across the total economy of 1.9%

What’s more the average number of hours work in a week was lower at the start of this year than last. The data suggest the total number of hours worked was just 0.5% up over the year.

The data shouldn’t be seen as being totally accurate. There are plenty of vagaries. But the clear message seems to be that the total hours worked in construction in the first quarter of 2015 were much the same as for the first quarter of 2014.

Taken at face value you might read that as very slow growth in construction. That would support a position slightly closer to the ONS output position than the trade surveys.

But that would forget a few shifts that are happening within the mix of work. Notably we are seeing a shift from repair and maintenance work to new work, which is less labour intensive. So, you’d expect then that for a given amount of output you’d need fewer people.

Also there has been a drop recently in the number of women working in construction. I’d be cautious about reading too much into this. There are many ways to read this data.

One obvious take on this dispiriting asymmetric movement in the employment in construction between men and women would be that firms are cutting back on administrative roles, where women are more commonly employed. The flip side of this is that jobs on site may well have risen faster than the aggregate figures suggest.

A further queering factor we should be aware of is the influence of migrant workers. A surge in overseas workers into construction would be slow to show in the figures. There has been a tendency for the survey data to under count new migrants in the workforce. So the picture we are seeing may be behind the real curve.

Taking all the above into account it may be that there are more people employed on the ground in construction and more productively (in a very crude sense of the notion) than the figures suggest.

But however you cut it the jobs figures don’t immediately support the idea of a rapid rise in construction. Though you’d expect them to lag rather than lead the trend in activity. They also don’t support a fall.

But one thing the figures do suggest is that there is tightness in the labour market and firms are responding.

Firstly, the number of unemployed former construction workers is at a historic low. Over the past 20 years there has been just one other quarter when the figures suggest unemployment was lower than the current 80,000 count. Secondly, we are seeing a shift back from self-employment to direct-employment.

Self-employment is down on a year ago. Direct-employment has risen moderately strongly. The bottom graph suggests that this could be both a response to fears over shortages and a response to rising wages associated with the boot now being more firmly on the foot of the worker rather than the employer.

So adding up all the above, just how fast is construction activity growing?

For my money I’d be cautious about being too precise. There will have been a surge in work associated with restocking. This kicked off when the Government chose to boost the economy as it flagged in 2012, through such moves as Funding for Lending and Help to Buy.

The increase in stocks is noticeable particularly in the accounts of house builders, where there is a higher level of work in progress. As that restocking surge, which seems to have kicked off late 2012 early 2013, weakens we should expect a slowdown in growth.

This does not mean that the industry is slowing in a general sense. Things are broadly on the up. But there is one big problem, the supply side and in particular skills.

We spent five or six years, needlessly in my view, depleting the supply side of the industry.

We will pay a high price for that. And for me at least it rather taints the pleasure of seeing more cash finally being invested in the built environment.


PS: I forgot to add in the BIS building materials data which shows, among other things, brick and block deliveries and production. Worth noting the easing in brick deliveries over recent months.


Why structural demographic challenges threaten house-building numbers

Brian Green

Much has been made of the latest English Housing Survey that shows homeownership among the young dwindling still further.

It’s a corker for the media. It has generated reams of copy in the press and numerous discussions on TV broadcasts and radio phone-ins.

But it ain’t news.

A bit like the “ageing population problem”, the decline in youngsters owning their own homes was evident decades ago if you cared to look at the statistics.

A favoured quip is that Margaret Thatcher created a generation of homeowners – just the one generation though.

In truth fast-rising homeownership easily pre-dates Thatcher. She did however cash-in on its popularity, promoted the trend and accelerated it by selling council housing.

Today many of those who rode the post-War tidal wave of swelling homeownership are surfing onto the sunbathed equity-rich shores of retirement. Sadly they leave behind them desperate would-like-to-be-homeowners splashing about deep in a trough waiting for the next wave to appear.

You might ask: Why was the media so slow to recognise this long-standing phenomenon? That would be pertinent. An obvious suggestion is that the middle classes have only recently felt a pinch felt many decades ago by poorer fellow citizens – those less active in political and media circles.

You might also reasonably ask: Why is the focus primarily on intergenerational fairness? Good question. There are serious intergenerational issue. They need addressing. But there are deeper structural problems beneath that are disguised by this shallow skim through the data. At least, I think there are. You may think differently.

Let me describe just one of these structural problems I feel are concerning.

The story starts with the top graph. It’s a favourite of mine. It shows for the past 40 years or so we have built one private new home for every 10 homes sold in the housing market in England and Wales as a whole.

Graphs on EHS 26 02 15What drives this is not fully clear, to me anyway. That’s why I like it so much. It tweaks my curiosity.

The link maybe in some way connected to planning. Maybe, as the graph seems to intimate, there is a connection to the collapse in social housing provision. Research is needed.

But it’s a remarkably strong and enduring link and as the market is currently structured it’s holding firm.

If we speculate that this link will continue to hold, there appear to be two options for boosting private sector house building.

We could discover what causes this link and break it favourably to boost the market share of new homes, or we could greatly promote more residential transactions.

Given we don’t really know what causes this link to hold (or at least I’ve not seen any solid explanation) it’s hard to know how to break it. So we’re left with finding ways to raise transactions.

Sadly, here, the English Housing Survey data hold bad news in the demographics. They point to things getting worse, because existing homeowners are likely on average to move less and they account for a major share of residential transactions.

The English House Survey and its predecessor the Survey of English Housing suggest that 60% of people that move into or within homeownership are previous homeowners. The second graph shows how this has been pretty consistent for some while. So the number of residential transactions is greatly influenced by the number of existing homeowners moving.

But why will they move less on average?

There’s the rub, the focus solely on the intergenerational unfairness and that young people are missing out on homeownership misses one important point. Older homeowners move much less than younger homeowners.

Let’s look at the stats and do some sums.

A quick analysis of the survey data on recent movers over recent history suggests you’re almost four times as likely to find a recent mover among householders under 45 years old than householders who are 45 and older.

Ok but why does this matter?

Compare 2000 with 2013. There were roughly the same number of homeowners in England and Wales. But on our figures (holding all other things than the age profile equal) the average likelihood of one moving was about 15% to 20% less in 2013 than in 2000.

This suggests a major source of residential transactions has shrunk fast (an underlying fall of about 10% in a decade) and was shrinking even as homeownership was rising.

From here the picture doesn’t get any brighter.

Low inflation will restrict house price rises, so the level of equity accumulation that promoted climbing the housing ladder among those in the generation now retiring may become a thing of the past. This suggests the propensity to move will be less among the young in the future.

Now I may be getting over concerned here, but my reading is that this (just one of a number of structural problems) will bear heavily down on transactions.

If that is so and the link between transactions and private house building remains stable we will, all other things equal, build fewer new private homes.

Talk all you like about demand being great and about a better planning system. The result would mean, as things stand, fewer homes built.


Reasons to be cautious over the latest construction output data

Brian Green

Last Friday the Office for National Statistics released final quarter data for construction output in 2014. It put growth for the year at 7.4%.

This, according to the official record, followed slightly anaemic growth in 2013 of 0.4%. The suggestion from these figures is that construction took off rapidly in 2014. 7.4% growth is pretty tasty.

But should we believe this version of recent history?

My advice would be no.

I suspect when the figures are settled later this year we will see a different pattern. Say growth anywhere up to 3% for 2013 and growth between say 4% and 6% for 2014.

This is not just a punt. There are good reasons to suspect this.

I can’t say I fully understand what’s going on, but clues can be found in tables 2a, 2b, 4 and 9a of the associated reference tables for the November and December data.

So, here’s my take.

Table 9a shows the implied output price indicator – a series of coefficients that are there to show the difference between the data unadjusted for inflation and data adjusted for inflation (tables 4 and 2b). This important adjustment means we can assess the industry output both in cash terms and equivalent volume terms.

TheImplied output price indicators graph graph shows the path of the indicator published in the latest release (for December) compared with the path in the release published a month earlier.

We see a strange dislocation in the latest data. Rather than the data suggesting a steady pattern of inflation we have a sudden drop to apparent lower inflation in January 2014. This clearly isn’t how inflation works, unless for instance there’s a sales tax increase or the like. Even then it’s unlikely to be that stark a jump.

Look then at the revisions to table 2b (the non-seasonally adjusted volume measure). Almost £2 billion has been added to the period January to November 2013 in the latest release compared with the previous. The upward revisions to table 4 (the non-seasonally adjusted current-price/cash measure) is just £384 million, if my maths is correct.

What is more significant in this argument is that there have been no upward revisions to the data for 2013 or earlier.

The upshot is that statistical changes to 2014 data have raised the estimated level of work done. But no revisions have been made to 2013.

So, why the revisions?

There are two possible explanations that pop into my mind for a major change in the implied output price indicator. Firstly there has been a change in the estimate of the inflation rate applied to construction output. Second there has been a change in the structure of the data that has shifted the implied inflation.

But why were revisions made to 2014 and not 2013, leaving an uncomfortable jump in the data in January?

The reason here is likely to be that the 2013 data is fixed, because it is tied to the national accounts (The Blue Book, which I understand to be locked until June).

This would mean adjustments can be made to the 2014 data as more and better information is available, but this new information cannot be applied to 2013 until the Blue Book is reopened.

The trouble is we now have an apparent bizarre set of numbers. The suspicion is that the inflation adjustment (real or implied) fixed into the 2013 data is too high.

What does this mean?

If we were to assume the data will eventually run smoothly across the two years (let’s assume the implied inflation comes in closer to the dotted red line in the graph) the effect would be to raise the constant price output figure for 2013. All other things being equal, this would do two things. Growth in 2013 would rise while growth in 2014 would fall.

Ultimately we end up at the same place, it’s just the route is a little smoother.

So why does it matter?

The truth is for most people it isn’t going matter a jot. But for people who analyse how the industry is performing it has profound implications. We rely on history to provide a clue as to what is happening and what we might reasonably expect to happen in the future.

The statistics are vital tools to help plan better and set policy better. Well that’s the theory, one to which I subscribe.

Bright prospects ahead for construction. That’s the forecasters’ view

Brian Green

UK construction by 2018 will have witnessed a five-year growth spurt not seen since the 1980s. That’s what is suggested by the majority verdict among the latest batch of industry forecasts.

Taking Construction Products Association forecast numbers, from 2013 to 2018 the industry output will have expanded by a quarter. Only in the post-War era up to the 1960s and in the late 1980s did construction enjoy growth of that magnitude over a five-year period.

This will, if it happens, put huge stress on the depression-depleted resources of an industry already looking to imports of materials and labour to cope with rising demand. Which is, perhaps ironically, one of the risk to the growth forecast.

This resurgence in construction since the start of 2013 has been down largely to fast expanding housing work, especially new build. In the seven quarters 2013 Q1 to 2014 Q3 new housing output rose by 40%. Much of this will be down to the boost from Help to Buy. There has been a longer term upswing since the darkest days of recession, which has seen the new housing output rise 80% since 2009 Q3.

The majority view among the forecasters is that growth in house building will remain strong this year, but ease in 2016. In terms of the value of output this will see all new house-building work rise above its 2007 peak this year.

Forecasts feb 2015The majority view is that all other sectors will grow over the next two to three years. But there is, among the four forecasts covered here, a dissenter from the full-steam-ahead view of the future. The Hewes forecast, which tends to take on board more of the downside risks, suggests solid growth this year, but a dip into recession in 2016. It expects most new-work sectors to flag.

Hewes takes the view that house building, the big driver of recent growth, will falter in 2016. It expresses concern about a downturn in the cyclical commercial market and does not share the other forecasters’ optimism that the talk of more infrastructure work will convert to a boost to actual construction output.

Its view on direct public sector spending on construction is similarly much bleaker than the other forecasts.

Set against the three other forecasts which appear fairly consistently positive in outlook, the view presented in the Hewes forecast appears very downbeat. But it is worth noting there is considerable divergence in views over each of the construction sectors.

This is perhaps most evident in the infrastructure sector where Experian expects an expansion of more than 40% compared with CPA at 30%, Leading Edge at 15% and a drop of 5% in the Hewes forecast.

Certainly the infrastructure sector is giving forecasters the biggest headache at the moment. There is much talk of work in the pipeline, but the uncertainty over the work is high.

The good news on uncertainty is that the downside risks look less worrying, despite yet another saga of confusion over what will happen in the Eurozone following the Greek elections. But as mentioned earlier, supply constraints may act as a dampener.

Importantly the UK economy does seem to have found a firmer footing since 2012. Then, in the face of flagging growth, the Government appears to have eased on austerity (despite rhetoric to the contrary) and it also pumped money into the system through Funding for Lending. This in turn supported Help to Buy. This boosted mortgage approvals and consequently house building rose to meet the expanded demand.

The overall effect of these policy tweaks seems to have been to turn an extremely dismal economic performance over the previous two years into something more solid.

History and the data suggest it is solid economic growth that pumps life into construction. For my money this does support the view that construction will see growth, unless the economy is hit by a nasty shock.

One other factor that supports economic growth and suggests a bolstered underlying demand for construction is the expansion in the population.

It’s hard to quantify the specific level of demand for construction created by a growing population, but why not let’s try to get a handle on the scale?

Let’s assume each extra person needs the same share of the built environment as those already here. On current figures that comes in at about £80,000.

(The ONS put a replacement value in 2013 on the total stock of UK built environment that is in use at about £5.2 trillion. That’s the gross capital stock figure. The net capital stock, which takes into account that some of it is well worn, came to about £3 trillion. That means there was in 2013 about £47,000 worth of built environment per person, which would cost about £80,000 to replace.)

The population is growing at between 400,000 and 500,000 a year at present, according to ONS estimates.

To meet that increase on our assumptions would take investment of £30 billion to £40 billion. That’s about a quarter to a third of the current investment in the built environment.

Back in the 1990s the population was growing annually by between 130,000 and 210,000. In very round figures this suggests investing between £10 billion and £20 billion a year to provide for population growth.

Boiling it all down the industry needs to be about £20 billion or so bigger than in the 1990s just to accommodate a faster growing population. Add in the backlog of work left as the industry shrank during the recession and there’s a hint at potential demand.

Naturally the relationship between the built environment stock and the population is not linear. On one hand we use buildings more efficiently, reducing the demand. On the other hand we want better buildings and more space so we need to spend proportionately more. In all that there’s the muddle of what buildings and structures we actually need to match the type of society and economy we want and how much we are prepared to invest.

But it’s worth noting the ONS estimate of the replacement value of the built environment has doubled in proportion the population since the 1970s.

The key message from that crude data doodling is there’s potentially very strong underlying demand for more buildings.

Not least among them would be more houses.

The big question, as always, is who will invest and how much to do what?

How old is the average construction worker?

Brian Green

A figure keeps cropping up that suggests the average age of a construction worker is in the 50s and the industry is getting older by the day.

That makes for a good scare story. But is it true?

The story came up again in a construction economics meeting I was at last week. One anecdote suggested the faces on site looked 10 years older than 10 years ago.

Could this be real, the effects of recession-related stress on hard-working construction folk making them look older, or perhaps a cognitive bias (for instance a form of recognition bias where we notice and remember people of our own type more than others)?

Let’s not forget also that the population is aging generally, so you might expect an industry to reflect this.

So what is the answer?

It’s not all that easy, because industries and occupations change and are reclassified so the data are not always that easily compared. Also not all construction trades work in construction and not all people that work in construction work on sites.

We can get construction-related occupations from the census. For simplicity I took “skilled construction and building trades” for 2001 and 2011.

I also happened to be in the British Library last week and hurriedly checked the 1951 census. I only had time to take the numbers by age for males categorised as “workers in building and contracting” and “painters and decorators”. This should provide a reasonable sample for illustrating the spread of ages within construction, although you might rightly argue that it may be biased towards younger people because the specification of skilled isn’t there and female workers were ignored.

I fiddled a bit with the age bands making simple assumptions to reallocate people to fit a consistent set of age bands for the three periods. This will not have made much difference to the general shape.

Older workersThe results (top graphs) show a reasonably similar pattern for each of the census years. The cumulative total by age shows that in 2011 as in 2001 and 1951 about 75% of construction workforce is younger than 52.

My estimate of the average age for construction workers is 41 years old in 1951, 38 years old in 2001 and 42 years old in 2011.

It’s probably risen a bit since then, but I’m not sure what data was used to provide an average age above 50.

The second graph is interesting and helps explain why you might sensibly think the average age of a construction worker has risen by 10 years over the past 10 years.

It shows that the peak age of construction workers has moved on by a decade. If we take the mode rather than the mean, the average has risen by about 10 years. 10 years ago when you visited a site the most common age would be in the 30s today it’s the 40s. So the reason you might think the typical construction workers is 10 years older is because it’s true.

But what’s happened since 2011 and what data might illustrate the shift in and out of the recession.

The third graph splits people by industry rather than occupation, but broadly it’s measuring a very similar group.

If we split the age bands into the core of 25 to 50 age group and those younger and older, the change does not look that worrying on this presentation. Comparing the near peak of June 2007 with June 2014 we see the changes are not that dramatic. The vast majority are still younger than 50.

Presented this way you might conclude that the problem has been overstated and it’s true that some of the figures pumped out do lean towards the apocalyptic.

But that would ignore the very severe threat on the horizon. This can be seen when we look again at the modal shift. Or, put another way, where the biggest group of workers sits on their construction working-life conveyor belts.

The overall age distribution for each of the 2001 and 2011 census years suggests that large numbers of workers leave the industry in their 50s. In 2001 the most common age for construction workers was between 30 and 40 years old, so there was plenty of working life in construction left in that group. In 2011 it was between 40 and 50 years old and that was four years ago.

If the pattern of the past continues plenty of these workers are now leaving the industry and we should expect the numbers retiring from construction to rise very rapidly unless ways are found to encourage them to stay on.

If ways are not found to retain older workers, they will have to be replaced in increasing numbers by new recruits if the industry is to avoid losing talent at an increasingly alarming rate.

Given that the industry lost about 400,000 workers during the recession, the task of rebuilding numbers will be tough enough without having to fill a gaping hole left by growing numbers of retirees.

This suggests that the industry should, if it is in anyway sensible, be looking not only to recruit more workers but also to find ways of usefully exploiting the talents of older employees.

Forecasts paint a brighter future for building, but infrastructure data clouds the picture

Brian Green

The latest batch of construction industry forecasts out this week paint a brighter picture of growth for building in Britain, but a confused picture for prospects in the infrastructure sector.

I’ll turn to the confusion later, but for now it’s safe to say that, taken as a whole, the forecasts reflect and seem to support the general improvement in confidence within construction.

Despite recurring concerns over persisting fragility within the global economy, Europe in particular, the Construction Products Association (CPA) suggest a strong bounce back over the next five years.

Forecast autumn 2014 aIt expects growth rates ranging from 3.3% and 5.3% for each of the next five years. This should swell construction by 23% in real terms from 2013 to 2018.

As the graph shows, Experian is equally as bullish over the next three years. Hewes provides the usual useful counterpoint, as this forecast tends to factor in more downside risk, so is inevitably much less optimistic.

All three are extremely bullish about housing in the near term and, while Hewes sees growth fading, the CPA takes the view that growth will continue through to 2018.

Experian and CPA also expect strong growth from the commercial sector, with growth of around 15% over the three years 2013 to 2016. Hewes takes a far more pessimistic view.

Overall new work is expected to be a bigger driver of construction growth than repair and maintenance over the next few years. This is consistent with strengthening growth in the economy and growing confidence among investors.

But the forecasters do see respectable increases ahead in repair and maintenance work.

Pulling all this together the forecasters all upped their expectations for building.

There is however one big twist in the tale of these forecasts this time around, the variation in expectations for new infrastructure work. Rather perplexing official data has led to big disparities in the forecasts for the sector.

Experian and Hewes show new infrastructure work falling this year. The CPA penned in growth of almost 9%.

What is extremely interesting and pretty unusual is that CPA appears to have stepped away from using the ONS construction output figures as its datum for new infrastructure work.

The forecasts says: “Recent statistics from the ONS report that Q2 infrastructure output was 8.2% lower than one year ago and new orders were 32.0% lower than a year ago. These declines contradict surveys within the sector that suggest increasing activity. As a result, the infrastructure forecasts are not purely based upon recent output but also take account of survey and pipeline evidence.”

The suggestion here is that the CPA suspects there may be a problem with the Office for National Statistics (ONS) construction output new work infrastructure series. And, indeed, the performance of the series has raised a few questions of late.

But the CPA decision to forecast away from the data currently presented in the ONS infrastructure series raises some intriguing issues.

Unless the figures are revised upward, for the official output figures to hit the CPA forecast for this sector, on my calculations new work infrastructure output in the final four months of this year would have to be 40% up on the final four months of last year.

That would be a phenomenal and, I sense, an unlikely turnaround in work on the ground.

Then again, a problem may be found in the data and the CPA view could end up matching the official figures through revisions to the back series.

But ultimately whether the CPA forecast and the ONS figures end up matching is just part of this puzzle.

What is perhaps of greater concern is whether there is actually a problem with the infrastructure figures or not. This is a moot point. It reveals just how hard it is to forecast change in construction industry activity and just how hard it is to know with certainty the level of work within the various parts of the industry.

Certainly civil engineering contractors have seen strong growth for a year or so. And there has been much rhetoric and bullish talk about investment in infrastructure. This all points to the data being misleading.

On the other hand we must consider what is actually happening within the industry. Inevitably some of the buoyancy civils firms feel is down to the rising tide of new building work and the ground works and services associated. Could it be this that is boosting civils work and disguising weaker infrastructure work?

Certainly, we have a problem in understanding how much infrastructure spending actually goes on construction work – that is how much goes to contractors suitably coded as being in construction and how much to other firms not classified as construction, such as process engineering firms.

A road job has a large construction element, a windfarm far less. The construction content of water projects will vary depending on the proportion spent on mechanical systems and controls.

There are of course other potential sources of confusion within the data classification and within the collection process.

Are we missing some specially-formed joint venture businesses in the sampling, or underplaying their importance?

Are firms not classified as construction undertaking what is construction work and so work is being wrongly allocated to, say, manufacturing?

Are firms correctly allocating construction works within the forms they fill in for the ONS?

There are a host of possible effects that can distort a data time series.Forecast autumn 2014 bCertainly a variation in the mix of work will have an impact.

So let’s out of curiosity compare the proportion of each subsector within new work infrastructure in the four quarters to Q2 2007 with the four quarters to Q2 2014.

We see there has been a profound shift in the mix of work. Road, water, sewerage and harbour works have declined, while rail and electricity work has increased.

Could it be that a big headline investment in electricity gives the impression of lots of work, but in reality only a low proportion of that work is recorded as construction?

These are questions that need research before we know if a problem with the ONS data is likely or not.

Ultimately without deeper knowledge it is extremely hard to know for sure if the ONS infrastructure time series is a reasonable or unreasonable reflection of the path of construction’s share of the investment in infrastructure.

It is certainly a conundrum and once again illustrates the extreme difficult in measuring each month how big the construction industry really is.


Note: the bottom graph has been replaced since first posting as it originally had 2017 not 2007 in the title.

Questioning data, questioning the value of data, glasshouses and stones

Brian Green

Last week’s ONS construction data release caused a few ripples when it showed output dipping in August.

It also sparked some sharp criticism from Chris Williamson, chief economist at Markit – the people that bring you the PMI surveys.

The second paragraph of his commentary reads: “We question the value of the official construction data due to the scale of revisions that occur after data are first release. The signals about the health of the sector and the economy as a whole can be utterly misleading as a result.”

I’m no shrinking violet when it comes to criticising statistics. But I wondered whether the comment was fair, balance or constructive. So is it?

The ONS release suggested a drop in output of 3.9% in August compared with July and a drop of 0.3% comparing August 2014 with August 2013.

It also showed a 5.5% dip in private housing between July and August, which surprised a few people.

Output Oct 2014 1For me there was no great surprise in the figures. Mind you, I wouldn’t have been shocked if the monthly figure went up. It’s an early estimate of one month’s data on the level of construction in various sectors. It is not a snapshot indicator of sentiment.

August was a bit wetter than usual, so it may have dampened output. The industry is in a state of change so volatility is expected. This is particularly true of house builders as they restock their production pipelines. Even when the construction industry is on a reasonably even keel the data are volatile.

Looking at average of output over three months probably gives a better picture. The three months to August showed growth of 1% on the previous three months 5.3% on a year ago. So the data clearly suggest underlying growth, with a possible hint at a easing in the growth rate of late. That is all clear from the top graph, which illustrates the volatility of monthly data.

Should you always expect to be going upward when you’re climbing a mountain? I don’t, not that I climb that many mountains.

What’s more would I, if I were running a construction-related business, be reliant on updates on the level of production at a GB aggregate level to a high degree of accuracy on a monthly basis? Well probably not. A general sense of where things are going at an aggregate level from a few sources will do fine, even if they are contradictory, along with a damn good detailed understanding of my particular markets. So what’s the problem?

What about the issue of revisions? They were pretty big this time around.

Revisions are a pain. But then again not revising the past when you learn that you misrepresented it (absolutely or relatively) presents its own issues, particularly if your information customer is me – someone who likes long data series with as much consistency as you can muster.

The scale of revisions we are told was partly down to a number of technical things, such as re-referencing the indices to 2011=100 to align with the National Accounts outputs and seasonal adjustment methods in the new processing system, plus the usual adjustments made to incorporate late data.

If you imagine all the elements that feed into or are related to the National Accounts as a huge multidimensional jigsaw that has to be, as far as possible, internally consistent, revisions are inevitable. When one bit moves others have to move.

Annoying as they are, I’ve learned to accept the regular revisions. Oddly, the upside is that in some odd way they seem to give me a better understanding of the strengths and weaknesses of the series.

To my mind, ultimately, all construction data are iffy. It’s just a question of how iffy and why.

Construction is a highly complicated industry to capture with simple measures. The projects are lumpy and extremely heterogeneous. The sectors are variable and hazy. The firms are all different shapes, sizes with very variable mixes of work.

Finding a neat way to capture all that in a few simple indicators presents the surveyor and statistician with a nasty task. Trying to get an accurate gauge on the precise level at any one time is even more devilish.

That’s what the ONS seeks to do with the construction output figures. For me, at least, it is less a short-term measure of direction of change than a useful gauge of level over time.

My approach on short-term trends tends to be to use what might be described as triangulation. I look at many surveys (including the ONS construction output and orders), assess as best I can how they match and how they conflict. I question their individual weaknesses and I try to assess how they fit with the broader context.

The Guardian used to run ads suggesting that it, as a newspaper, looked beyond the meaning one might ascribe to one observation and took in the bigger picture before seeking to interpret what was actually happening.

The first clip might show a dodgy looking fellow pushing an old lady. Your immediate thought was “mugger”. The second clip (the reveal) would then show the “thug” bravely pushing the vulnerable lady away from falling bricks. Ah, not a thug, but a hero.

Context is all, beware cognitive bias, etc, etc.

As with people’s intentions, we can read data and get the meaning completely upside down.

A lesson I learned long ago was to question all data. When seeking meaning from data it’s worth bearing in mind among other things, how they were collected, the assumptions in the methodology, the survey size, the motives of the respondents, how the survey data is translated into an estimate of volume or change, the impact and treatment of occasional factors, weights and price or seasonal adjustments.

You then have to look out of the window, away from the spreadsheet at the real world.

With these thoughts in mind let’s question the construction survey produced by Mr Williamson’s firm, Markit.

To provide comparison and a bit of context I have compared the Markit/CIPS construction survey headline indicator with the monthly construction survey provided by the Bank of England Agents.

Output Oct 2014 2What we notice is that since March 2010 the construction industry has grown on the Markit measure in 47 out of 55 months. However, when there has been a slowdown recorded it has been relatively slight. The Bank of England Agents however did not measure growth until November 2010. They then recorded a slump from October 2011 through to June 2013 (21 months).

If we take the period March 2010 to March 2013 the average Markit/CIPS score is 52.6 (suggestive of sound growth) against the average for the Bank of England Agents of -0.6 (suggestive of modest decline).

I will leave those in the industry to decide which they feel provides the more representative depiction of their interpretation of the path of GB construction.

I will however draw from an unrelated dataset, employment. Between March 2010 and March 2013 100,000 jobs were lost to the industry, that’s almost 5%. Now that could happen with an expanding industry. But it would be unusual for construction, particularly as the more labour-intensive repair and maintenance work seems to have been stronger than the less labour-intensive new-build work over the period.

I’ll not go into the potential methodological issues with Markit’s measure in any detail. I can’t. I’ve asked in the past for a full rundown of the methodology. I don’t recall receiving it.

I have a couple of outside observations though, I’d need to be convinced that procurement directors are necessarily the best placed to gauge business activity within construction (some may well be) and I would instinctively be wary over the PMI sample size given the heterogeneity and the muddled regional spread of construction firms.

Interestingly, I have found the ONS transparent and open to and accepting of criticism over its construction data. The statisticians and their approaches come in for regular scrutiny at the Consultative Committee on Construction Industry Statistics, not least from me. I can see it hurts them at a personal level. But that is the price we pay when we accept our mistakes as we try to get things right.

That brings me to glasshouses. Ideally they are great for transparency. Not so good a place in which to throw stones.

Construction recovery stalls, but the forecasts remain bright

Brian Green

The latest official output data from the Office for National Statistics show growth apparently stalling in the second quarter.

This may seem at odds with trade surveys and media commentary which tend to point to construction booming. It’s not really.

Despite the zero growth recorded by ONS for output in the second quarter of this year, at the risk of doing a Michael Fish, I think we can be confident that the industry is pretty much set on an upward path. There’s nothing startling on examining the data that would suggest otherwise.

Though I’m not sure I’d call it a boom, more a rebound – finally.

You’d hope so. The gap between output at peak and today is still 10%. Forecasters expect the industry may just about have recovered the lost ground by 2016.

Construction output 2014 q2The latest ONS data release does, usefully in my view, provide a reality check. The release reminds us that recoveries can be bumpy and uneven affairs. Indeed, the data release prompted me to make this point by cheekily tweeting that if it were not for housing-related work construction would be in recession.

But even non-domestic construction is, I think, actually on the mend. It tends to take a bit more time to recover. The data supports optimism that the recovery is starting to spread into corners so far left untouched. But while work in the pipeline is pumping up, at this stage recovery in work on the ground will remain patchy.

So suggestions that things are hunky dory in construction will inevitably jar with many folk who are still struggling.

The ONS figures overall put output in the second quarter up 4.5 % on a year ago. That’s sound growth. But this is down to some sectors in some regions recovering far quicker than others. This is best characterised by the strong housing growth supporting boom-time growth rates in London.

Housing and non-housing output 2014 q2London, incidentally, is where most national policy makers and opinion formers reside. It’s understandable that their view of the national picture is shaped by what they see around them. Many will not be able to look beyond the effects of housing output being double its 2007 level in London to appreciate the effects in other regions of housing output being 30% to 40% down on 2007 while public sector is shrinking and private commercial and industrial building activity is still fairly fragile.

As to the reasons for this recovery in construction, there’s little magical, unexpected or extraordinary. By and large when there’s sustained growth in gross domestic product there tends to be growth in construction. This holds true in the UK as it does in Argentina, Botswana and China.

After a long period flatlining the UK economy has woken up and enjoyed a year and a half or so of sustained and fairly robust growth. Forecasts suggest this period of growth will remain strong for some time yet. So there is a platform that supports growth in construction.

The latest set of industry forecasts support this. Two, Experian and Construction Products Association, expect strong growth from here, expanding the industry by about 10% over two years. Growth will be particularly strong for new work. The Hewes forecast shows growth, but it is weaker and expected to evaporate in 2016.

The Hewes forecast tends to factor in more of the downside risks rather than taking a strictly central position. One of the growing risks noted by Hewes is the rising cost of construction. This, Hewes argues, will restrain the construction growth of output in volume terms – the normal measure used.

Hewes is also pessimistic on a return to growth for the commercial sector. It forecasts persistent falls for a couple of years, compared with annual rises of about 4% to 5% forecast by Experian and Construction Products Association.

But even the more pessimistic take on risk from Hewes shows the industry improving.

Forecasts summer 2014There are upside risks to these forecasts. If they are realised and release greater confidence to build, they might easily out gun those on the downside. There’s huge potential demand for construction if the confidence and finance can be found. The slump in building work will in some quarters have created a backlog of work that needs addressing. The need to address the nation’s energy supply being a major issue. Furthermore the population continues to grow adding pressure for more homes and infrastructure increases.

There are also structural changes in the economy relating to the increased use of information technology. This is changing how we use buildings and where they need to be located. The changes should result in demand for construction as the built environment is adapted to suit.

Naturally the General Election in 2015 represents a real risk. But by comparison to 2010 the risks may be stacked on the upside.

The last election was fought on the battleground of austerity. That is not good for capital spending. This time around it seems that all political parties are increasingly emphasising the benefits of investment in housing and the nation’s transport infrastructure. In the bidding war for voters there is a fair chance this may push spending on construction up rather than down the agenda.

Downside risks remain. When and how fast will interest rates rise and how will rises impact on investment and consumer spending? What might unwinding quantitative easing mean for investment? The current recovery is reliant on consumer spending, despite low earnings growth, how long before we see a more balance recovery? Will the Eurozone troubles remain contained? Will fear over capacity constraints restrain investment in construction? How will global political instability impact on economic growth? What effect might independence for Scotland have on construction? And there are plenty more.

There will always be risks, but in the round construction is in a much stronger position than it has been for some time. Work is easier to find and will become so for ever more firms in the industry. And there are plenty of reasons for optimism in the longer term.

That, however, doesn’t mean everyone is seeing improvements and everyone will. More importantly, while work may be easier to find, the industry has a tough job on its hands rebuilding its own infrastructure, particularly its skills based, as it drags itself out of the slough of long and painful depression.

Are we witnessing the start of another housing problem?

Brian Green

There’s something, no lots of things, desperately disturbing about today’s stories (examples here and here) telling of Government panic over potentially unflattering house-building figures released just before the General Election.

Where to start?

Let’s start with “starts”. These seem to be the housing figures in question.

On 20 February I tweeted: “For those not familiar with the terminology: you live in a housing completion, you don’t live in a housing start”

It was a jibe in response to a press release on the latest house building figures. They showed housing starts in England up 23% in 2013 on 2012. They also showed completions down 5% 2013 on 2012.

Mr Eric Pickles and his advisers chose to crow on the starts figure to gain immediate impact with the headline: “Housebuilding at highest for 6 years.”


To understand the starts figures you need to consider stock and flow and restocking effects in the house building world. You also need to consider what’s been happening on the ground in planning. (I did a blog with some charts that in part covers this point here.)

A better measure of how well house building has been doing in these official figures is the number of homes completed. I’ll not hang around explaining why even these are no perfect measure of success in terms of solving the housing problem.

I will however say that housing starts data are useful forward indicators for what might be built. So are planning approvals, net reservations, mortgage transactions and a host of other data. But they are not an accurate predictor of what will be built and when. And they are probably worse than some of the other indicators mentioned.

Starts figures are also very volatile. Naturally they swung up rapidly from a very low base. This produced impressive sounding percentage gains, the type politicians can’t help seizing upon.

Why did we see such a sharp upswing? Firstly because house builders needed to restock their much depleted production pipelines, which (collectively) had been run down during the recession. Secondly, because new land was coming through, after a few years of a slowing in applications and approvals, there were more sites to be opened, more starts to be made. Thirdly, because the production levels had to be readjusted upward to meet current demand the rate of starts had to rise. And there are other more subtle reasons for the rapid rise in starts.

Any smart fellow would realise that this probably would lead to an initial surge and then things would settle down, if not fall off slightly, but remain at a higher level.

The completion figures however relate to sales. Looking forward these will rise, but more slowly and more steadily than starts as the industry emerges from recession and transactions pick up.

The eagerness of the Government to claim credit over its opposition for “fixing” the housing market had them pick starts over the less impressive completions figures.

Now it seems they have twigged to the possibility that they will be hoist by their own petard, as the volatile starts figures might just dip at an inconvenient time. Poetic don’t you think?

This reveals four things, if not more:

  • The shallowness of politics and its concerns with how it looks rather than what it does;
  • The vanity among certain politicians, matched only by their delusion over the effectiveness of their actions;
  • The abuse to which politicians will put otherwise useful statistics;
  • The apparent crass stupidity over the workings of the housing market at the heart of the department notionally charged with solving its problems.

I’ll stop before I just repeat myself, but less politely.

There is of course another disturbing aspect to all this if the media reports are correct. The fear within the Government that it might look silly now appears to be driving housing policy.

To be quite honest, I’m a bit surprised by this. I’d naturally expected a simpler solution to this obvious potential trap, a switch within the department to ditch the starts data as the prime measure to highlight progress in house building and place the emphasis on completions. Obviously the growth rate would be much poorer and the level appalling relative to the past, but the likelihood is that it will at least be heading in the right direction as we enter full-scale election fever.

However disingenuous that might be it is preferable to tailoring a policy that impacts on the lives of thousands of people and is central to the economy to meet some spurious Government PR target.

But what do I know about politics?

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