One of the recurring themes in England's ever thrilling devolution debate is that things work differently across the Pennines. To the west of the backbone of England, it's the great cities of Manchester and Liverpool that get the international recognition, while Lancashire, the county they came from, gets forgotten.
To the east, we're told, things are different: since Yorkshire is world famous, and Leeds and Sheffield (forgive me) aren't, it makes sense for any devolution settlement to be to the ancient county as a whole.
This may or may not be true. What does seem clear, though, is that – even if Yorkshire has the global recognition that the Yorkshire First Party claim – this isn't doing it much good when it comes to international trade.
Check out this graph produced by the Centre for Cities' principal economist Paul Swinney, based on data uncovered for the think tank's new Cities Outlook report. On the vertical axis is the amount 62 British cities export per job. On the horizontal one is the share of private jobs in each city that are in a foreign-owned business.
These are rough and ready measures: in a smaller city, they can be distorted by one major employer which exports a lot of high value goods (hello Sunderland, hey there Hull). But they nonetheless give you a sense of how international a city's economy is.
The Yorkshire cities have been shaded blue. See if you can spot the subtle pattern.
Click to expand.
In all, of the 10 cities with the lowest exports per job, five of them are in Yorkshire. That’s more than half of the nine Yorkshire cities in the dataset.
Why this should be is not exactly clear. Part of the explanation is that there's a loose correlation between these two figures (a correlation coefficient of 0.42, since you ask). That makes sense: foreign-owned businesses are more likely to trade internationally, so more of the former will likely mean higher exports per job, too.
But that doesn't so much explain the trend as push the need for explanation upstream a bit: why have the nine Yorkshire cities included here seen so little foreign-direct investment?
It could be relatively poor infrastructure: the biggest airport in the north, and busiest rail link to London, are both the other side of the Pennines. Or perhaps it’s a fluke of the data: most of the Yorkshire cities included here are in that depressed M62 belt, and Sheffield is the poorest major city in the UK.
But that wouldn't really explain Leeds which has, historically, been the richest major city in the north, yet still ranks 54th out of 62 cities on exports per job.
So maybe, just maybe, the Yorkshire brand isn't quite the international powerhouse its promoters like to think.
You can read the full Cities Outlook report here.
Jonn Elledge is the editor of CityMetric. He is on Twitter, far too much, as @jonnelledge.