The latest data included 15 planes that were destroyed during strikes in late September and October at Taqba Air Field in northern Syria, and a drone that was hit in mid-March. The aircraft were captured by ISIS after a major battle against Syrian government forces, and were subsequently targeted by the coalition. Pentagon spokeswoman Cmdr. Elissa Smith did not have details on the type of aircraft that were targeted, but Bellingcat, a crowd-sourced news site, reported in August that the captured planes included Mig-21s.

Previous releases did not include the aircraft, and Smith said that this likely had to do with changing data from the daily battle damage assessments.

So far, the U.S. military has spent $1.83 billion on operations in Iraq and Syria through March 12, with an average daily cost of $8.5 million, according to the Pentagon.