Treasury Secretary Steve Mnuchin racked up almost $1 million in military flights last year at taxpayers’ expense, according to a new report.

In a report issued Thursday, the watchdog group Citizens for Responsibility and Ethics in Washington, which investigated Mnuchin’s travels through Freedom of Information Act requests, found Mnuchin took eight separate trips on military aircraft between spring and fall 2017.

The group criticized Mnuchin for apparently making no effort to schedule commercial flights or smaller military planes.

“The public still has no reasonable explanation for why Secretary Mnuchin apparently has never used commercial aircraft, while his predecessors did; why his travel is not designed to minimize costs by, for example, scheduling confidential calls when he is not on a short domestic flight; or why he needs military aircraft that can accommodate 120 passengers when his travel manifests contain far fewer names,” the report said.

Mnuchin’s travel expenses have come under fire previously, including a trip with his wife in August where they watched the solar eclipse from the rooftop of Fort Knox, Ky., and a request — which was later withdrawn — to use a military jet for their honeymoon in Europe.

The Treasury Department’s inspector general investigated Mnuchin’s use of military aircraft, and in October said his travel violated no laws.

The watchdog report Thursday noted that previous Treasury secretaries have generally flown commercial.

A number of other Trump administration Cabinet members have been criticized for their lavish spending, including Interior Secretary Ryan Zinke, who has been investigated for his use of expensive charter flights; Housing and Urban Development Secretary Ben Carson, whose office recently canceled a $31,000 dinning-room set for his office; and Health and Human Services Secretary Tom Price, who resigned in September after accruing about $1 million in charter flights at taxpayers’ expense.