The Departed. Photo: Drew Angerer/Getty Images

In its first year, the Trump administration posted a turnover rate fit for a season of The Apprentice. National security adviser Michael Flynn didn’t last a month. Communications director Anthony Scaramucci barely put in a week before publicly deriding the White House’s chief strategist’s (alleged) affinity for auto-fellatio. That strategist, Steve Bannon, followed chief of staff Reince Priebus and press secretary Sean Spicer back to the private sector by summer’s end.

In total, 21 of the administration’s 61 senior officials were either allowed to resign, fired, or reassigned in 2017. That 34 percent first-year turnover rate is the highest in at least four decades — and double the previous record set by the Reagan administration — according to Kathryn Dunn-Tenpas of the Brookings Institution.

“Not only is the percentage double, the seniority of people leaving is extraordinarily high,” Dunn-Tenpas told the Wall Street Journal. “That’s unprecedented to me. The first year always seems to have some missteps on staffing, often because the skills that worked well running a campaign don’t always align with what it takes to run a government. In this case, it’s a president with no experience in government and people around him who also had no experience … So it’s not surprising that it’s higher than normal, but it’s still surprising it’s this high.”

The George W. Bush, Obama, and Clinton administrations lost 6, 9, and 11 percent of their first-year senior staff members, respectively.

History suggests the Trump White House could bleed staff at an even higher clip next year. Reagan’s turnover rate jumped to 40 percent in 1982, while Clinton bid adieu to 27 percent of his top aides in 1994, and George W. Bush saw 27 percent of his depart in 2002. Trump’s current deputy national security adviser Dina Powell and deputy chief of staff Rick Dearborn both plan to head for the exit early next year. Omarosa Manigault Newman, the former Apprentice contestant turned miscellaneous White House adviser, will resign on January 20.

The Trump administration is bound to have trouble finding replacements for its defectors — or at least competent ones. The president’s indecorous demagoguery has alienated a significant portion of the GOP’s “wonk” class, while his fragile ego has led him to reject many #NeverTrumpers who learned to stop worrying and love the Trump presidency. Making matters worse, the Mueller probe threatens to impose legal costs on anyone who decides to take a gig at 1600 Pennsylvania Avenue.

Until this month, (relatively) high-functioning corporate managers had a major incentive to tolerate the many, obvious downsides of working for Donald Trump — the opportunity to shape tax-cut legislation to their industry’s advantage. But with that deed done, and the prospects for major legislation in 2018 looking dicey, Treasury Secretary Gary Cohn is reportedly eyeing a return to Wall Street. And it seems unlikely that there will be many Goldman Sachs partners eager to take his place.

Meanwhile, Trump has left hundreds of high-level positions across the federal government unfilled, while hundreds of civil servants have fled the EPA and State Department.

This White House has never been known for its competence. But historically high turnover rates are poised to undermine its proficiency even further. The administration’s lack of expertise has already contributed to a humanitarian crisis in Puerto Rico. It could abet several more disasters in the years to come.