This analysis revealed a lot of surprising conclusions, including the following:
Today's government spending levels are indeed too high, at least relative to the average level of tax revenue the government has generated over the past 60 years. Unless Americans are willing to radically increase the amount of taxes they pay relative to GDP, government spending must be cut.
Today's income tax rates are strikingly low relative to the rates of the past century, especially for rich people. For most of the century, including some boom times, top-bracket income tax rates were much higher than they are today.
Contrary to what Republicans would have you believe, super-high tax rates on rich people do not appear to hurt the economy or make people lazy: During the 1950s and early 1960s, the top bracket income tax rate was over 90%--and the economy, middle-class, and stock market boomed.
Super-low tax rates on rich people also appear to be correlated with unsustainable sugar highs in the economy--brief, enjoyable booms followed by protracted busts. They also appear to be correlated with very high inequality. (For example, see the 1920s and now).
Periods of very low tax rates have been followed by periods with very high tax rates, and vice versa. So history suggests that tax rates will soon start going up.
Read more: THE HISTORY OF TAXES: Here's How High Today's Rates Really Are