Yeh.. My Mum is 80? (or something..It would be imprudent of me to reveal her true age even tho she goes line dancing a few times a week... !! (happy birthday mother!) She was a child during the war. How many people in a population of 60 million in the UK are over 80? Less than a million.
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I see part of your problem.
WWII ended in 1945. Anyone alive then, by definition, lived through WWII. Which means that we are counting people ~67 or older.
And according to
https://www.cia.gov/library/publications/the-world-factbook/geos/uk.html, unless you have some proof that unless there are 9,341,628 people between the ages of 65 - 67, your figure is way off.
Did you see what I did there? I referred you to an webpage which has some authority.
It could easily have been a book or something, but the point is you don't have to take my word for it.
This is that citation thingy for which I kept asking you. Not that, given your performance so far today I am hopeful you will be able to produce, but perhaps you will surprize me.
BTW, you can munge the URL should you choose to use the web, and someone will post the correct citation for you. So, for example, I could post h t t p s://w w w .cia.gov/library/publications/the-world-factbook/geos/uk.html if I were unable to directly post links.
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