The United States has spent around $8 trillion waging war in the two decades of bloodshed since the attacks on Sept. 11, 2001, according to an updated estimate from the Costs of War project at Brown University. The new figure, released Wednesday, suggests that the U.S. has spent trillions more on post-9/11 wars than previously thought. The project reached its estimate by adding up an array of war expenditures including increased spending from the Defense and State Departments, ballooning contractor costs, current and future care payments to veterans, and anti-terrorism spending from the Department of Homeland Security. Future costs are likely to remain high due to ongoing disability payments to vets and interest payments on money borrowed to fund the wars.

The researchers also estimated that the post-9/11 wars have directly killed around 929,000 people. “The Costs of War Project hopes that this accounting, and our other work, promotes transparency and facilitates informed conversations about current and future wars,” the authors wrote in the report.