Comment by Muromec
Rule of thumb — if a bank already was there and dealing with things 30 years ago, it likely has some cobol left.
Generalizing — if the company had enough need for it 30 years ago, was big enough to but a mainframe and the thing they used it for barely changes — chances are it’s still there, if the company is still there.
Banks absolutely do have it in house, in a dedicated secure site with a fence and a moat
And insurance, and there are telcos still having boxes spinning. And places dealing with inventories or airlines and whatever, or healthcare. If databases helped and it was around before 1992 it might still be running some cobol.