Your tax preparation software may tell you how much you owe in federal income taxes for 2013, but it won't tell you how your money is spent by the federal government.

No worries. The National Priorities Project did the math for you, based on actual federal spending in 2013.

Broadly speaking, for every dollar you pay in federal income taxes, about half goes to military spending (27%) and spending on federal health programs (22.7%). The latter covers everything from Medicare and Medicaid to the Children's Health Insurance Program.

The next biggest chunk of your income taxes (13.8%) goes to paying interest on U.S. debt.

After that, 9.8% is used to support unemployment and jobs-related programs, such as career training and temporary assistance for needy families.

Veterans benefits get about 5% of your federal income taxes, as do food and agriculture programs.

Running the government, including overhead costs and spending on various agencies and offices, such as the FBI and immigration services, comes in at 4.5%.

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Four percent, meanwhile, goes to housing programs, such as community development block grants, while 2% is spent on education, including everything from Head Start programs to Pell Grants.

And less than 2% is spent on each of the following: science, international affairs, transportation, and energy.

Here's what that all means in dollars-and-cents spending for someone who paid $15,000 in federal income taxes for 2013:

Military: $4,064.34

$4,064.34 Health: $3,409.19

$3,409.19 Interest on the debt: $2,080.26

$2,080.26 Unemployment and Labor: $1,468.10

$1,468.10 Veterans benefits: $758.00

$758.00 Food and Agriculture: $756.88

$756.88 Government: $682.39

$682.39 Housing and community: $598.84

$598.84 Education: $304.69

$304.69 Energy and Environment: $278.17

$278.17 International Affairs: $226

$226 Transportation: $204.03

$204.03 Science: $168.11

See how the total you paid in federal income taxes for 2013 breaks down.

Note: The National Priorities Project's calculations exclude payroll taxes. Payroll taxes fully pay for Social Security benefits. But they only cover a portion of Medicare's expenses -- the remainder is covered by general federal revenue and premiums.