We know that taxes on the very rich are at a historic low right now, which will go even lower if Mitt Romney wins. But how low, exactly?

All the detailed studies I know of go back only to 1960. I’ve written about Piketty-Saez; the 2010 Economic Report of the President (pdf) also provided estimates, not taking into account corporate taxes:

All these estimates show that taxes on the rich are the lowest they have been in half a century. But what about before 1960? Well, we know that the top marginal tax rate was even higher in the 40s and 50s than in the 60s; and it was very high by modern standards through much of the 30s too.

So I think it’s safe to say that taxes on the rich are currently lower than they have been for not 50 but 80 years. And if Mitt Romney gets his way, we’ll bring those taxes down to levels not seen since Calvin Coolidge.