The wars in Iraq and Afghanistan have cost U.S. taxpayers nearly $5 trillion so far, and that total could rise even higher in the years to come, according to new calculations released by independent researchers late last week.

That total includes not only the costs of equipment and personnel in those countries, but also State Department spending to help local populations, Department of Homeland Security spending linked to the wars and Department of Veterans Affairs services that expanded as troops returned home.

In a report for Brown University's Watson Institute for International and Public Affairs, study author Neta Crawford called the total "so large as to be almost incomprehensible," but noted the dollar figures are only one part of the costs of war.

"A full accounting of any war's burdens cannot be places in columns on a ledger," she wrote in the report. "From the civilians harmed or displaced by violence, to the soldiers killed and wounded, to the children who play years later on roads and fields sown with improvised explosive devices and cluster bombs, no set of numbers can convey the human toll of the wars."

But researchers said they undertook the project to provide a clearer understanding of the financial expenditures related to the wars, given "much less comprehensive accounts of U.S. war spending" from federal agencies.

Of the $4.79 trillion total calculated in the report, about $1.7 trillion comes from direct war appropriations over the last 15 years. The White House has already requested another $65 billion in overseas contingency funding as part of the fiscal 2017 budget.

Crawford also includes in her costs of war a rise in defense base budget spending related to the overseas conflicts of about $733 billion, and another $565 billion in related State Department and Department of Homeland Security programs.

And the total also includes more than $1.2 trillion in increased and future costs for veterans’ health care. That doesn’t include other VA benefits, such as the post-9/11 GI Bill and home loans.

Crawford notes that future interest on debts associated with unpaid war costs "will likely be many trillions of dollars," further adding to the total.

"Even if the U.S. stopped spending on war at the end of this fiscal year, interest costs alone on borrowing to pay for the wars will continue to grow apace," she wrote.

The full report is available online at the Institute’s web site.

Leo Shane III covers Congress, Veterans Affairs and the White House for Military Times. He can be reached at lshane@militarytimes.com.