The most important graph in British economics

Birmingham: somehow less than the sum of its parts. Image: Getty.

“Is there a relationship between city size and productivity?” the Centre for Cities asked in February 2015. The blog takes two reports and hundreds of pages from the OECD and distils it down to the biggest topic in city economics today – does being bigger make you richer?

It’s a question that I’ve been asking myself since I was 19, when I moved to London and Paris to study. I’ve been asking myself the same questions consciously since I was 25, and I couldn’t find a job in science after finishing a PhD in Leeds.

And now, thanks to some more great work by Centre for Cities, I can get a lot closer to answering the question than the OECD did.

I think that these questions are going to matter even more in the coming years because, for a number of reasons.

  • Manchester and Birmingham, the UK’s two biggest underperformers, have since elected their own mayors. Both cities are determined to make up the 30 per cent gap between them and comparable cities in the EU.
  • Richard Florida’s recent book, The New Urban Crisis, has started informing debates in the UK in the same way that Edwards Glaeser’s Triump of the City did five years ago.
  • Theresa May’s government has said it is determined to “build a country that works for everyone”. It will try to expand the UK’s successful industrial strategy beyond South-East England to more of the country. The loudest voices in opposition to this will claim that focusing on London will always deliver greater returns due to its size.

So what does the data say? Do agglomeration benefits exist? Are bigger cities richer?

French and German cities show agglomeration benefits

In France and Germany there’s a pretty clear answer: yes. The line of best fit slopes up with size. It is statistically significant. It’s the same in the USA. (GVA is a measure of how much economic value is created in a place.)

Click to expand.

Cities in Scandinavia and the Low Countries show large agglomeration benefits

There aren’t enough cities in Sweden, Denmark, Belgium, and The Netherlands to do a proper regression. But their economies are similar enough, so I just lump their cities together.

And there’s a very strong agglomeration benefit.

Click to expand.

Spanish and British cities show no agglomeration benefits at all

Spain and the UK are different. Size doesn’t matter. In fact in the UK the best fit line slopes down a bit, but not significantly so.

Click to expand.

The most important graph in British economics

And now the most important graph. The one’s that’s frustrated me all my life. The one that I don’t accept that the UK has ever tried to fix. And the one that makes taking lessons from books written in America and applying them to UK cities risky.

Remove London from the graph of UK cities, and the larger a city gets, the poorer it is. This doesn’t happen in France or even in Spain.

Click to expand.

I think that we can fix this. The Northern Powerhouse is the right strategy; metro mayors will help, moving things the way that we moved 10 per cent of the BBC to Manchester will help; and investing in transport and science in big cities where businesses want to grow will help.

But my faith in all those things is based on a belief that we can make our country more German, French, American, and Dutch in terms of agglomeration benefits. I hope that I’m right.


Want the data and graphs? They're here in Excel. Ecept France which broke.

Tom Forth is an associate at ODILeeds. This article first appeared on his blog.

 
 
 
 

“Stop worrying about hairdressers”: The UK government has misdiagnosed its productivity problem

We’re going as fast as we can, here. Image: Getty.

Gonna level with you here, I have mixed feelings about this one. On the one hand, I’m a huge fan of schadenfreude, so learning that it the government has messed up in a previously unsuspected way gives me this sort of warm glow inside. On the other hand, the way it’s been screwing up is probably making the country poorer, and exacerbating the north south divide. So, mixed reviews really.

Here’s the story. This week the Centre for Cities (CfC) published a major report on Britain’s productivity problem. For the last 200 years, ever since the industrial revolution, this country has got steadily richer. Since the financial crash, though, that seems to have stopped.

The standard narrative on this has it that the problem lies in the ‘long tail’ of unproductive businesses – that is, those that produce less value per hour. Get those guys humming, the thinking goes, and the productivity problem is sorted.

But the CfC’s new report says that this is exactly wrong. The wrong tail: Why Britain’s ‘long tail’ is not the cause of its productivity problems (excellent pun, there) delves into the data on productivity in different types of businesses and different cities, to demonstrate two big points.

The first is that the long tail is the wrong place to look for productivity gains. Many low productivity businesses are low productivity for a reason:

The ability of manufacturing to automate certain processes, or the development of ever more sophisticated computer software in information and communications have greatly increased the output that a worker produces in these industries. But while a fitness instructor may use a smartphone today in place of a ghetto blaster in 1990, he or she can still only instruct one class at a time. And a waiter or waitress can only serve so many tables. Of course, improvements such as the introduction of handheld electronic devices allow orders to be sent to the kitchen more efficiently, will bring benefits, but this improvements won’t radically increase the output of the waiter.

I’d add to that: there is only so fast that people want to eat. There’s a physical limit on the number of diners any restaurant can actually feed.

At any rate, the result of this is that it’s stupid to expect local service businesses to make step changes in productivity. If we actually want to improve productivity we should focus on those which are exporting services to a bigger market.  There are fewer of these, but the potential gains are much bigger. Here’s a chart:

The y-axis reflects number of businesses at different productivities, shown on the x-axis. So bigger numbers on the left are bad; bigger numbers on the right are good. 

The question of which exporting businesses are struggling to expand productivity is what leads to the report’s second insight:

Specifically it is the underperformance of exporting businesses in cities outside of the Greater South East that causes not only divergences across the country in wages and standards of living, but also hampers national productivity. These cities in particular should be of greatest concern to policy makers attempting to improve UK productivity overall.

In other words, it turned out, again, to the north-south divide that did it. I’m shocked. Are you shocked? This is my shocked face.

The best way to demonstrate this shocking insight is with some more graphs. This first one shows the distribution of productivity in local services business in four different types of place: cities in the south east (GSE) in light green, cities in the rest of the country (RoGB) in dark green, non-urban areas in the south east in purple, non-urban areas everywhere else in turquoise.

The four lines are fairly consistent. The light green, representing south eastern cities has a lower peak on the left, meaning slightly fewer low productivity businesses, but is slightly higher on the right, meaning slightly more high productivity businesses. In other words, local services businesses in the south eastern cities are more productive than those elsewhere – but the gap is pretty narrow. 

Now check out the same graph for exporting businesses:

The differences are much more pronounced. Areas outside those south eastern cities have many more lower productivity businesses (the peaks on the left) and significantly fewer high productivity ones (the lower numbers on the right).

In fact, outside the south east, cities are actually less productive than non-urban areas. This is really not what you’d expect to see, and no a good sign for the health of the economy:

The report also uses a few specific examples to illustrate this point. Compare Reading, one of Britain’s richest medium sized cities, with Hull, one of its poorest:

Or, looking to bigger cities, here’s Bristol and Sheffield:

In both cases, the poorer northern cities are clearly lacking in high-value exporting businesses. This is a problem because these don’t just provide well-paying jobs now: they’re also the ones that have the potential to make productivity gains that can lead to even better jobs. The report concludes:

This is a major cause for concern for the national economy – the underperformance of these cities goes a long way to explain both why the rest of Britain lags behind the Greater South East and why it performs poorly on a

European level. To illustrate the impact, if all cities were as productive as those in the Greater South East, the British economy would be 15 per cent more productive and £225bn larger. This is equivalent to Britain being home to four extra city economies the size of Birmingham.

In other words, the lesson here is: stop worrying about the productivity of hairdressers. Start worrying about the productivity of Hull.


You can read the Centre for Cities’ full report here.

Jonn Elledge is the editor of CityMetric. He is on Twitter as @jonnelledge and on Facebook as JonnElledgeWrites

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