I am not that old but the did have ratio write-offs. The largest was 1017-1 so if you put a dollar in your company you got to deduct 1017. You could also deduct all interest on credit cards, hell everything was deductible get a copy of 1950’s tax return.
I watch bryan gumbal on good morning America (that goes way back) they had a guy put his tax return on tv. He made over 1 million dollars and after doing his taxes he got a refund of over 300,000.
Credit cards in the '50s? No such thing. We had store charge accounts, but the only major credit card was American Express and you had to pay a fee for that and pass a rigorous exam for credit. And AMEX required the card to be paid in full each month. Generally the only people who had an AMEX card were people who traveled for business -- and that was in the 60s.