The latest instalment of our series, in which we use the Centre for Cities’ data tools to crunch some of the numbers on Britain’s cities. 

One of the joys of this column is when I stumble onto something genuinely surprising. I’ve spent so long trying to come up with variations on the phrase “Well I never, it’s the north-south divide again!” that on those rare occasions when I find something weird, I am suffused with a genuine sense of delight.

Anyway, here’s the skinny. This week, I decided to look at how the economies of Britain’s major cities – London, Edinburgh and the 10 Core Cities – have grown over the last couple of decades. The Centre for Cities’ data on Gross Value Add – essentially, how much economic value is being created in each city, in pounds sterling – comes from the Office for National Statistics (ONS), and goes back to 1998.

Direct comparisons between the cities would make trends difficult to spot: the data isn’t per head, so simply by virtue of being so much bigger London would dwarf all the others and render trends impossible to see. To fix that, I’ve expressed the size of each city’s economy as a multiple of its 1998 value: when a city crosses the line labelled “2”, its economy is now double the size it was in 1998.

So, here’s the chart. You may wish to expand it to look at the key.

Click to expand.

The least surprising thing here is that London tops the charts, even on this relative growth measure. Since 1998, the capital has boomed, in terms of both economics and population (the two may be connected). By 2016, its economy was worth more than 2.3 times the amount it was worth just 18 years earlier. That’s equivalent – assuming I haven’t cocked up the maths – to an average annual growth rate of about 4.8 per cent, which is really not to be sniffed at.

The next two on the list probably aren’t that surprising either. Edinburgh is a rich city and a regional financial centre; Cardiff an increasingly important media hub. More importantly, both became government centres in 1999, as the new devolved Scottish and Welsh administrations moved in. Little wonder that this has brought economy benefits. Look at the left hand side of the graph, indeed, and you can see that Cardiff was, for a while, the fastest growing major city in Britain.

Beyond that, though, things start getting counter-intuitive. Because the next fastest growing major city economy in the years since 1998 turns out to be… Liverpool.

This doesn’t really fit the narrative, does it? When we talk about rebalancing England’s economy away from London, it tends to be Manchester that comes to mind – or, at a push, Birmingham. But the latter turns out to have been one of the slowest expanding city economies since 1998, with an average annual growth rate of just 3 per cent (only Nottingham has been slower, and then only slightly). Manchester fares better, but it’s still only mid-table, at 3.7 per cent.

The true Northern Powerhouse since 1998 has been Liverpool. With an average annual growth rate of 4.2 per cent, it’s one of only five of the 12 cities to have doubled the size of its economy since 1998, passing that mark by 2015. Between 1998 and 2009-10, in fact, it was the fastest growing major city in the UK. Then there was the slight matter of the crash and the austerity which followed, but even then it’s bounced back.

This data raises a number of questions to which I simply don’t have the answer. What drove Liverpool’s relatively stellar performance? And why did nobody notice it? By the same token, what went wrong in Birmingham? Have I just mucked up the data? If you have any thoughts, please do let me know.

I’m also aware that these numbers start at a faintly arbitrary point, and that if we started the clock in another year things might look different. So, next time in this slot, I’m going to look at the same data, but this time starting at the crash. Bet you can’t wait.

You can explore the full Centre for Cities dataset here.

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

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