Dorris, it's undeniable that the US was doing better when tax rates on higher incomes were higher. It's an association and you can't say for sure which comes first, the chicken or the egg. Maybe times were so amazingly good and prosperous that disposable incomes remained marvelous almost independent of tax, especially since keeping up with the Jonses is easier when everybody is on the same wicket (English term). Of course these figures come from before the parasitic types began shaving enormous sums from the economy in exchange for nothing of value to anybody else and insisting that the Founding Fathers wanted the rich to pay less tax and continuing guzzling long after their bellies were stuffed.
"... They ne'er cared for us
yet: suffer us to famish, and their store-houses
crammed with grain; make edicts for usury, to
support usurers; repeal daily any wholesome act
established against the rich, and provide more
piercing statutes daily, to chain up and restrain
the poor. If the wars eat us not up, they will; and
there's all the love they bear us."
-- Shakespeare: Coriolanus, Act 1, scene 1