You're mistaken and given your responses elsewhere I think you're either confused or arguing in bad faith.
The mean tax rate paid by the top 0.1% of earners in 1979 was just over 40%. This fell to about 25% in 2010.[1] Marginal rates followed a similar trend. Meanwhile the US Gini coefficient rose from .415 in 1979 to .476 in 2012.[2] This implies that the top quintile pays a greater share of Federal taxes because they're proportionally richer than the other quintiles. The poor don't pay much Federal tax because you can't get blood from a stone.
[1] http://online.wsj.com/public/resources/documents/r42729_0917..., page 3
[2] https://www.citylab.com/life/2014/05/mapping-three-decades-i...