capital-gains-and-growth.png chart displayed above shows top tax rates on long-term capital gains and economic growth (measured as the percentage change in real GDP) from 1950 to 2011. If low capital gains tax rates catalyzed economic growth, you’d expect to see a negative relationship–high gains rates, low growth, and vice versa–but there is no apparent relationship between the two time series. The correlation is 0.12, the wrong sign and not statistically different from zero. I’ve tried lags up to five years and also looking at moving averages of the tax rates and growth. There is never a statistically significant relationship.

Does this prove that capital gains taxes are unrelated to economic growth? Of course not. Many other things have changed at the same time as gains rates and many other factors affect economic growth. But the graph should dispel the silver bullet theory of capital gains taxes. Cutting capital gains taxes will not turbocharge the economy and raising them would not usher in a depression.

Low capital gains tax rates do accomplish one thing: they create lots of work for lawyers, accountants, and financial geniuses because there is a huge reward to making ordinary income (taxed at rates up to 35%) look like capital gains (top rate of 15%). The tax shelters that these geniuses invent are economically inefficient, and the geniuses themselves might do productive work were the tax shelter racket not so profitable. And the revenue lost to the capital gains tax loophole adds to the deficit, which also hurts the economy.

I know what my accountant is doing with my income/capital gains, and he's not a genius.icon_lol.gif