Something we've looked at a couple times. Link after the jump.
From Asia Times, July 20:
A former top US military intelligence officer writes in a limited-circulation report:
We don’t know what the real numbers are on either side; casualties don’t really count, remaining soldiers count. This is, I think, the real source of worry for Ukraine. The Ukrainian economics minister noted that Ukraine is short 6 million working age adults. Estimates of the current actual population are around 30 million – or less.
Just before the war started Ukraine had a plan to build an army of 400,000 with an additional 900,000 in reserves, based on a nominal population of 43 million. With a real population of 30 million – 6 million working age adults gone – those numbers become very difficult....
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November 3, 2022"The wicked weaponization of Ukrainian refugees "
"How you gonna keep 'em down on the farm after they've seen Wroclaw?"
That's me, quoting myself from the introduction to: "Are Ukrainian Farmers an Endangered Species?":
Probably.
There are a few things going on that point in that direction. First you have the country's total fertility rate at 1.4, only two-thirds of the 2.1 replacement rate, tied with poster child Japan in the who's-going-extinct competition. And lower even than famously-low-birthrate-Russia, which at 1.8 has a comparative population boom. So there will literally not be enough people to take up the job.