They stayed there until Kennedy/Johnson cut them to 70% in the 1960s. The 1981 Reagan tax bill cut them to 50%, and the 1986 tax reform cut them to (around) 33%. Clinton put them back up to 40%.
Since the economy performed better during WWII (and during the subsequent postwar boom), and during the Clinton boom years than they did in the Reagan/Bush I years, on the surface there seems to be little correlation between marginal tax rates and economic performance.
You may be right, though, in that few people probably ever actually pay tax rates in excess of 40% or 50% due to loopholes and evasion.
The economy was fairly strong during the Truman and Eisenhower eras, but nowhere near the expansion of the 1960s. Conservatives want live babies so they can raise them to be dead soldiers. - George Carlin
