90%.
That was the tax rate for the rich (top 8%) for 8 years under Eisenhower. The United States saw it's greatest improvements in infrastructure, standard of living, and the birth of the middle class during that time.
In each progressing administration, taxes on the wealthy were lowered while taxes on the middle class increased, the rich got richer and the middle class got left behind turning us into what we are today: a society of working poor dominated by a very small extremely wealthy upper class.
I got ridiculous in the 1980's.
As late as 1971, Muhammad Ali and Joe Frazier got $2.5 million a piece to fight. They both cleared less than $1 million.
Johnny Carson and other TV stars were paid deferred money to avoid the high tax rates all at once.
None of those people starved with their multiple property estates and fancy cars.
JFK cut the top tax rate from 91% to 67% to spur growth in the early '60's.
It was a brilliant idea that has been totally abused with subsequent adminstrations. They had ballanced budgets every year back then. Then came Vietnam, OPEC & oil company collusion and St. Reagan's military buildup and endless wars.
Now, everything over budget is on Uncle Sam's credit card.