Economist Paul Krugman wants you to know that Republicans are still lying about Obamacare. Not only is it helping to insure millions that might not otherwise have access to coverage, it’s doing it for cheaper than was ever thought possible.

In an op-ed piece for the New York Times, Krugman calls out the GOP for its deception over the Affordable Care Act (ACA). Rep. Pete Sessions (R-TX) recently said the cost of the healthcare law was “unconscionable” and “simple multiplication” proved that the expansion in coverage costs $5 million per recipient.

“But his calculation was a bit off,” said Krugman, “namely, by a factor of more than a thousand. The actual cost per newly insured American is about $4,000.”

The ACA is actually costing taxpayers about 20 percent less than expected, according to data from the Congressional Budget Office.

“A senior member of Congress should know that,” Krugman pointed out, “and he certainly has no business making speeches about an issue if he won’t bother to read budget office reports.”

Republicans try to paint the ACA as the worst thing to happen to American health care. But in the five years since it went into effect, more than 16 million Americans have been insured.

The ACA also hasn’t turned out to be the job destroyer the GOP had hoped it would be, either.

“In 2011, the House even passed a bill called the Repealing the Job-Killing Health Care Law Act,” said Krugman. “Health reform, opponents declared, would cripple the economy and in particular cause businesses to force their employees into part-time work.”

Instead, “private-sector job growth actually accelerated, to a pace we haven’t seen since the Clinton years,” and “the number of workers who want full-time work but can’t get it … has dropped sharply.”

This hasn’t stopped the Republican leadership from continuing to spew their false rhetoric, Krugman said. Earlier this month, for example, probable presidential candidate Jeb Bush called the ACA “the greatest job suppressor in the so-called recovery.”

Despite all the data showing how effective the ACA has been, the GOP is still fishing for horror stories to back their bogus claims.

“Early last year, Americans for Prosperity, a Koch brothers-backed group, ran a series of ads featuring alleged Obamacare victims,” said Krugman, “but not one of those tales of woe stood up to scrutiny. More recently, Representative Cathy McMorris Rodgers of Washington State took to Facebook to ask for Obamacare horror stories. What she got instead was a torrent of testimonials from people whose lives have been improved, and in some cases, saved by health reform.”

“We live in an era in which politicians and the supposed experts who serve them never feel obliged to acknowledge uncomfortable facts, in which no argument is ever dropped, no matter how overwhelming the evidence that it’s wrong,” Krugman concluded.

“And the result is that imaginary disasters can overshadow real successes. Obamacare isn’t perfect, but it has dramatically improved the lives of millions. Someone should tell the voters.”