National Bureau of Economic Research:

The top 0.1 percent was composed of 160,000 families with average 
wealth of $72.8 million. All told, they owned 22 percent of the nation’s
wealth.

Meanwhile, the bottom 90 percent -- 144 million families with average
wealth of $84,000 -- owned only 22.8 percent of the wealth.

In other words, the top 0.1 percent and the bottom 90 percent of U.S.
households own virtually the same share of all the nation's wealth. Is there a problem with this number?

Non-Partisan Congressional Tax Report Debunks Core Conservative Economic Theory

The conclusion?

Lowering the tax rates on the wealthy and top earners in America donot appear to have any impact on the nation’s economic growth.

This paragraph from the report says it all—

“The reduction in the top tax rates appears to be uncorrelated with saving, investment and productivity growth. The top tax rates appear to have little or no relation to the size of the economic pie. However, the top tax rate reductions appear to be associated with the increasing concentration of income at the top of the income distribution.”

http://www.forbes.com/sites/rickungar/2012/11/02/non-partisan-congressional-tax-report-debunks-core-conservative-economic-theory-gop-suppresses-study/#2839b7ac431b