The top-earning 1 percent of Americans will pay nearly half of the federal income taxes for 2014, the largest share in at least three years, according to a study.

According to a projection from the non-partisan Tax Policy Center, the top 1 percent of Americans will pay 45.7 percent of the individual income taxes in 2014—up from 43 percent in 2013 and 40 percent in 2012 (the oldest period available). (Tweet this)

The bottom 80 percent of Americans are expected to pay 15 percent of all federal income taxes in 2014, according to the study. The bottom 60 percent are expected to pay less than 2 percent of federal income taxes.

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While the top 1 percent pay a larger share of taxes, they also earn an outsized share of income. According to the Tax Policy Center, they earned 17 percent of expanded cash income in 2014. (Some studies have given higher estimates for this group's share of income depending on their different definitions of income.)