Millions of Americans filed their 2012 federal income tax returns Monday "but few know what happens to their tax dollars," said Joe Comerford, executive director of the National Priorities Project.
The project's Tax Day 2013 shows "exactly how each federal income tax dollar was spent in 2012, down to the penny," Comerford said.
The military received 26.45 cents from every federal tax dollar.
Third on the list was interest on the federal debt, receiving 13.6 cents, she said. Education programs accounted for 3.5 cents while science took a penny.
The breakdown draws attention to some of the central budget issues facing the United States, including military spending and healthcare costs, said Mattea Kramer, a senior research analyst with the National Priorities Project.
"Tax Day is a chance for Americans to see where their taxes are going, and to decide if Washington's priorities match up with their own priorities for our nation," Kramer said.
Eighty-six percent of tax-filers said they plan to have their taxes filed by Monday's deadline, a Rasmussen Reports national telephone survey released on Tax Day indicated.
Rasmussen surveyed 1,000 U.S. adults Friday and Saturday. The margin of error is 3 percentage points.
The total includes 72 percent who had filed by Saturday, up 11 percentage points from the end of March but down from 78 percent this time last year, Rasmussen said.
Another 14 percent said they intended to get them done Sunday or Monday while 7 percent said they would seek an extension.
The Libertarian Party, quoting the Tax Foundation, said in a release Americans must work to pay their taxes until Thursday before they can begin working for themselves, based on the total federal, state and local tax burden of $4.22 trillion.
If federal borrowing is factored in, Tax Freedom Day would be May 9, the Libertarian Party noted.
When total spending by all levels of government is considered, the Libertarian Party said the burden of government will reach $6.16 trillion for 2013, meaning Tax Freedom Day wouldn't be until June 6.