Members of the 133rd Engineer Company, Maine Army National Guard stand in formation before being reunited with their families, July 1, at the Augusta Armory, after a year-long deployment to Afghanistan in support of Operation Enduring Freedom. Credit: Spc. Adam Simmler 121st Public Affairs Detachment / U. S. Army National Guard

The nearly 20-year American combat mission in Afghanistan was the United States’ longest war. Ordinary Americans tended to forget about it, and it received measurably less oversight from Congress than the Vietnam war did. But its death toll is in the many tens of thousands, and generations of Americans to come will be burdened by the cost of paying it off.

As the U.S. commander for Afghanistan, Gen. Scott Miller, relinquished his command in Kabul on Monday, here’s a look at the U.S.-led war in Afghanistan, by the numbers.

Much of the data below from Linda Bilmes of Harvard University’s Kennedy School and from the Brown University Costs of War project. Because the United States between 2003-2011 fought the Afghanistan and Iraq wars simultaneously, and many American troops served tours in both wars, some figures as noted cover both post-9/11 U.S. wars.

The longest war

Percentage of U.S. population born since the 2001 attacks plotted by al-Qaida leaders who were sheltering in Afghanistan: Roughly 1 out of every 4.

The human cost

American service members killed in Afghanistan through April: 2,448.

U.S. contractors: 3,846.

Afghan national military and police: 66,000.

Other allied service members, including other NATO member states’: 1,144.

Afghan civilians: 47,245.

Taliban and other opposition fighters: 51,191.

Aid workers: 444.

Journalists: 72.

Afghanistan after nearly 20 years of US occupation

Percentage drop in infant mortality rate since U.S., Afghan and other allied forces overthrew the Taliban government, which had sought to restrict women and girls to the home: About 50.

Percentage of Afghan teen-age girls able to read today: 37.

Percentage of Afghanistan districts and district centers that the Taliban says it controls as Western forces withdraw: More than  one out of three.

Oversight by Congress

Date Congress authorized U.S. forces to go after culprits in Sept. 11, 2001 attacks: Sept. 18, 2001.

Number of times U.S. lawmakers have voted to declare war in Afghanistan: 0.

Number of times lawmakers in Senate Appropriations defense subcommittee addressed costs of Vietnam War, during that conflict: 42

Number of times lawmakers in same subcommittee have mentioned costs of Afghanistan and Iraq wars: 5.

Number of times lawmakers in Senate Finance Committee have mentioned costs of Afghanistan and Iraq wars, since Sept. 11, 2001: 1.

Paying for a war on credit, not cash

Amount President Harry Truman temporarily raised top tax rates to  pay for Korean War: 92 percent.

Amount President Lyndon Johnson temporarily raised top tax rates to pay for Vietnam War: 77 percent.

Amount President George W. Bush cut tax rates for the wealthiest, rather than raise them, at outset of Afghanistan and Iraq wars: At least eight percent.

Estimated amount of direct Afghanistan and Iraq war costs that the United States has debt-financed  as of 2020: $2 trillion.

Estimated interest payments on that $2 trillion so far (based on a higher-end estimate of interest rates): $925 billion.

Estimated interest costs by 2030: $2 trillion.

Estimated interest costs by 2050: $6.5 trillion.

The war ends. The costs don’t.

Amount Bilmes estimates the United States has committed to pay in health care, disability, burial and other costs for roughly 4 million Afghanistan and Iraq veterans: $1.6 to $1.8 trillion.

Period those costs will peak: after 2048.

Story by Ellen Knickmeyer.