I was curious so I looked it up. According to this article the top 10% pay 68% of all taxes.
http://www.heritage.org/federalbudget/top10-percent-income-e...
http://www.heritage.org/federalbudget/top10-percent-income-e...
Here's another take on U.S. taxation: https://www.americanprogress.org/issues/tax-reform/news/2011...