In the past week, President Barack Obama's administration overturned a decades-old policy toward Cuban immigrants, forged two major agreements to address racial bias in big-city police departments and approved an unexpected cut in mortgage premiums for hundreds of thousands of low-income and first-time home buyers.

Officials even made time, after years of lobbying, to add the rusty patched bumble bee to the list of endangered species.

In the final days before President Obama leaves office, administration officials are rushing to complete dozens of tasks that will affect millions of lives and solidify the president's imprint on history. But in many cases, their permanence is uncertain, and President-elect Donald Trump is already pledging to undo some of them after taking office.

"He is clearly using executive power aggressively and trying to do as much as possible in his final days," Princeton history and public affairs professor Julian Zelizer said in an email. "It is clear that a president who was once reluctant to use the power of his own office has changed his heart, especially now that he sees a radically conservative Congress and Republican president-elect are getting ready to dismantle much of what he has done."

On Thursday alone, the administration designated three new national monuments and expanded another two in sites ranging from a forest in the Pacific Northwest to a school for freed slaves in South Carolina; took away one of the special immigration privileges Cubans arriving in the United States without visas have enjoyed for 50 years; announced sanctions designations against 18 senior Syrian officials for their role in the use of chlorine as a chemical weapon in 2014 and 2015; awarded the Presidential Medal of Freedom to Vice President Joe Biden; and accused Fiat Chrysler of cheating on national emission standards for some of its diesel trucks.

For weeks, congressional Republicans and members of the Trump transition team have questioned why the White House is pressing ahead given that the GOP will control both the executive and legislative branch for at least the next two years.

On Dec. 5, 23 GOP senators wrote Obama a letter asking that his administration "cease issuing new, nonemergency rules and regulations given the recent election results of November 8."

"It is our job now to determine the right balance between regulation and free market principles and make sure that our federal government no longer stands between Americans and financial success," they wrote.

Many departments have also accelerated hiring in recent weeks, hoping to bring on as many employees as possible in case Trump proceeds with a planned freeze for federal employees. On Tuesday, House Oversight and Government Reform Committee Chairman Jason Chaffetz, R-Utah, wrote the heads of 18 agencies, asking them to provide details on their current hiring practices.

Both Trump and Vice President-elect Mike Pence have vowed to reverse some of Obama's key policies as soon as they take office. But it will be nearly impossible to erase all of them in the months and years ahead, and to achieve the maximum impact, Trump will have to accept new limits on his own power.

The Obama administration's race toward the finish line isn't completely out of the ordinary. Last-minute regulatory actions also spiked in 2008 and in 2000, said Sam Batkins, director of regulatory policy at the conservative American Action Forum, which has long been tracking White House regulations.

But since Oct. 1, Obama has finalized as many economically significant rules - ones with an estimated economic impact of at least $100 million - as George W. Bush did in his final four months in office.

"We find routinely that politics influences things, and this is just a manifestation of it," Batkins said. "We see how politics can bend these levers of policy."

More broadly, Obama has finalized at least 571 major rules while in office, nearly 62 percent more than Bush did during his two terms. And half of the major rules the White House Office of Management and Budget reviewed during the first five-and-a-half years of the administration had an economic impact of at least $1 billion, said Daniel Pérez, a policy analyst at the Regulatory Studies Center at George Washington University.

The tempo of federal regulation can work both ways, Batkins noted. While the Obama administration has been feverishly publishing new regulations in the wake of November's election, the same White House wasn't so eager to produce new regulations in the run-up to Obama's reelection in 2012. That October, by Batkins's count, just four rules came out of the White House.

The president and his aides have been unapologetic about the burst of new policies in recent weeks.

"The administration has made a concerted effort to complete important work that was started months or even years ago," said White House spokesman Patrick Rodenbush in an email, adding that when it comes to its most recent rules, "we have followed the same rigorous practices and principles used to develop and review regulations that have been upheld throughout the entirety of this administration and previous administrations."

Housing and Urban Development Secretary Julián Castro, who did not brief members of Trump's transition team before announcing Monday that the Federal Housing Authority would cut interest rates, told reporters that he had "no reason to believe this will be scaled back," adding that the change "offers a good benefit to hard-working American families out there at a time when interest rates might well continue to go up."

But Ben Carson, whom Trump nominated to succeed Castro, told lawmakers Thursday he was "surprised to see something of this nature being done on the way out the door, which of course has a profound effect."

"Certainly, if confirmed I'm going to work with the FHA administrator and other experts to examine that policy," Carson said.

The White House's sense of urgency is probably well founded, given Trump's commitment to try to roll back the policies of the Obama era. And Obama took much the same approach after assuming office in 2009, essentially halting former president George W. Bush's pending regulations.