It’s common knowledge the wars in Afghanistan and Iraq have cost the American taxpayer an exorbitant amount of money. The U.S. government’s lack of transparency to determine the true expense fuels wild speculations.

So far, estimates vary between $1 and $2 trillion. Since there are so many different agencies and departments involved makes it even harder to pinpoint an accurate number. However, a recent study by the Center for Strategic and International Studies (CSIS) reveals these estimations might be excessively conservative, and the true cost might amount to almost $6 trillion.

The CSIS report examines the FY2001-FY2019 time frame and all military and civilian funds allocated to fight or support the Afghanistan and Iraq war efforts. Report authors credibly present costs of up to $2.1 trillion–but this amount doesn’t include numerous programs and projects. The authors project actual costs of $5.9 trillion, and predict by the end of FY2023,  the outlay will reach $6.7 trillion.

Additionally, the CSIS report calculations account for direct and indirect costs. For example, funds spent by the U.S. State Department for foreign aid, or the Department of Veteran Affairs for veterans‘ support.