But we've been doing this for a while.

WE TRIED A FLAT TAX
The first income tax in the United States came about with the Revenue Act of 1861. A flat 3 percent tax on income above $800 was used to fund the Civil War and repealed 11 years later. In 1894, a new flat federal income tax was ruled unconstitutional by the U.S. Supreme Court. It was not until the 16th Amendment was ratified in 1913 that the federal income tax finally stuck for good.

FEW PEOPLE OWED AT FIRST
Before World War II, few individuals or families owed income taxes. Due to a high personal exemption, only 1.1 percent of working-age people filed a return, according to the Tax Foundation, and about 17 percent of those filers did not have to pay income taxes.

MANY PEOPLE PAY NO TAX NOW
According to the Tax Policy Center think tank, 44.3 percent of tax filers owed no individual income tax or had negative taxable income in 2016.

TAX PREP TIME ADDS UP
According to the IRS, the average time it takes to complete a Form 1040 is 16 hours; a 1040A takes seven hours; and a 1040EZ takes five hours. Overall, the average is 13 hours. In 2016, the IRS processed 152.25 million individual tax returns, equivalent to about 82.5 million days' worth of prep time.

TAX FREEDOM DAY
According to the Tax Foundation, Americans collectively had to work until April 24 last year -- 114 days -- to pay the country's tax burden. On a state-by-state basis, Connecticut residents had to work the longest, until May 21. Residents of Tennessee had the earliest Tax Freedom Day, April 6.

TOP EARNERS PAY
According to the Tax Policy Center, the top 1 percent of earners in the United States paid 42.4 percent of all federal income taxes in 2016. The top 0.1 percent paid 20.8 percent.