The Trump administration is paying about 154,000 employees not to work as a result of novel resignation incentives offered to federal workers since Inauguration Day, the government’s human resources arm said on Thursday.

That estimate is the first comprehensive disclosure from the government about the scale of President Trump’s effort to downsize the federal work force.

Still, the figure represents just a portion of the total number of workers who have left the federal government since the beginning of the Trump administration — only those who accepted an offer to resign early in exchange for many months of pay. It does not include the thousands of people who were laid off or fired.

While the Trump administration has not made public a complete picture of the cuts, the work of Mr. Trump and his Department of Government Efficiency under Elon Musk amounts to the largest reduction to the federal work force in the modern era. The government employed roughly 2.3 million nonmilitary workers at the start of the year.

A spokeswoman for the Office of Personnel Management said that as of June, about 154,000 employees had resigned or retired early with the promise of being paid through Sept. 30 or Dec. 31, depending on the offer. The Washington Post reported the figure earlier.

The Partnership for Public Service, a nonprofit that works to promote best practices in the federal government, had estimated the total number of departures — voluntary resignations, layoffs and firings — to be around 148,000 as of July.