A record 21.3 million people enrolled in health insurance plans through the Affordable Care Act’s marketplaces during the annual open enrollment period, President Joe Biden announced Wednesday.

The number represents a more than 30% increase from the previous year, when 16.3 million Americans signed up, according to the White House.

In total, 9 million additional people have enrolled in plans through HealthCare.gov or state-based marketplaces since Biden took office three years ago.

The open enrollment period for this year ran from Nov. 1 to Jan. 16. The administration had already announced earlier this month, based on data through Dec. 23, that the sign-up record had been broken.

Health policy experts have attributed the increase in enrollments largely to federal subsidies for people purchasing plans. The subsidies were included in two pieces of major legislation spearheaded by Biden: the American Rescue Plan and the Inflation Reduction Act. 

“It’s no accident,” Biden said in a statement Wednesday about the record number of sign-ups through the Affordable Care Act, commonly referred to as “Obamacare.” “My actions to protect the Affordable Care Act and lower premiums continue to make a big difference. And the American people have made it clear: they don’t want the Affordable Care Act weakened and repealed – they want it strengthened and protected.”

According to the White House, the subsidies have lowered health care premiums for millions of Americans by an average of $800 a year through 2025. Eighty percent of consumers can find plans for less than $10 a month, the Biden administration said.

Biden urged Congress to make the subsidies permanent and criticized Republicans who continue to say they want to repeal the Affordable Care Act, passed in 2010 under then-President Barack Obama.

“Over the last decade, extreme Republicans in Congress have blocked efforts to lower health care costs, and they’re still trying to end the Affordable Care Act, just as my predecessor tried and failed to do,” the president said. “Repealing the Affordable Care Act would throw these 21 million people off their coverage, and end Medicaid coverage for millions more."

Former President Donald Trump, the front-runner for the Republican nomination this year, said in November he is “seriously looking at alternatives" to the ACA. It was a campaign promise he failed to deliver on in his first term after three Republican senators voted in 2017 to save the law.

“The cost of Obamacare is out of control, plus, it’s not good Healthcare,” Trump wrote on his Truth Social platform.

Despite repeated promises to do so dating back to his time in office, Trump has never presented a detailed plan for replacing the Affordable Care Act.