John Jones is unemployed.
He gets Jobseekers allowance through the Llandudno JobCenter. His benefit is clearly noted as one paid in Wales.
When he visits the JobCenter on Monday he sees a job that fits his profile so he applies for it. The interview is on Friday, so in preparation he goes to Asda to buy a new suit, he buys the cheapest one, of course (he is on benefits).
Despite buying the suite in ASDA Llandudno, Wales, and paying VAT on his purchase, that VAT isn't a tax paid in Wales; the tax will be paid in Leeds, where ASDA has its accounting office.
The person who serves him on the clothing counter lives in Wales and works in Wales, but her income tax will also be paid in Leeds, because her pay check will be taxed in head office.
John gets the job, so he comes off the Welsh benefit take, but his job is also taxed in England so he doesn't become part of Wales' contribution to taxation.
Of course it is swings and roundabouts.
John's new job may involve manufacturing a component that is created in Wales and is exported to the rest of the world, something that is measured on a Wales basis and will show up as a plus in Welsh exports.
But remember that cheep suit he bought in Wales in order to go to the interview? That was probably imported through England, so statistics that show that Wales has a good balance of payments between imports and exports might not be as good as it first looks.
The fact is that the UK produces economic statistics for UK reasons. The UK would never, ever produce economic details that promoted nationalism.
Data that proved beyond doubt that Scotland or Wales or, Heaven forbid, even England would be better off outwith the UK will never, ever be available.
Of course the complete lack of proper data is a means to an end. Without the data we can't make a proper decision based on economic policy as to whether nationalism is good for our nation's economy, or a recipe for disaster. That is precisely why the data isn't available!
We can argue these economic points till kingdom come, but why should we?
Shouldn't the campaigns for English, Scottish, Cornish and Welsh self determination come from a fire in the belly rather than from a chequebook?