Health and Human Services Secretary Robert F. Kennedy Jr. defended President Donald Trump’s faulty calculations on prescription drug prices with some bad math of his own on Thursday.
Previously, Trump has said he would reduce prescription drug prices by “1,000%, 600%, 500%, 1,500%,” prompting critics to note that this was mathematically impossible.
As HuffPost’s Ed Mazza has explained, “Reducing the price by 100% would make the drugs free. Reducing it by ‘1,000%, 600%, 500%, 1,500%,’ as Trump said, would make the cost negative dollars ― with the drug company essentially paying people to take the medication.”
Kennedy attempted to explain Trump’s flawed use of percentages during an Oval Office meeting on Thursday.

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A Democrat senator “was ridiculing President Trump for his math, and she was saying it’s mathematically impossible to have any drug drop by 600% cost, which he had claimed,” Kennedy said. “I said, ‘Well, if the drug was $100 and it raised the price to $600, that would be a 600% rise. Well, if it drops from $600 to $100, that’s a 600% savings.’”
Both of those calculations are inaccurate.
If a drug’s price were to go from $100 to $600, that would be a $500 uptick, or a 500% increase. If a drug’s price were to go from $600 to $100, that would be a $500 discount, or roughly 83% in savings.
Kennedy’s statement effectively endorsed Trump’s incorrect interpretation of percentages, an approach the HHS official characterized as a “mathematical device.”
On Wednesday, Kennedy used a similar explanation when Sen. Elizabeth Warren (D-Mass.) pressed him about Trump’s drug price statements during a Senate hearing.
“President Trump has a different way of calculating … there’s two ways of calculating percentage. If you have a $600 drug and you reduce it to $10, that’s a 600% reduction,” Kennedy said. As commentators noted, that amount of savings would actually represent a roughly 98% reduction, not 600% as he suggested.
Trump made the same point on Thursday as well.
“There are two ways of calculating it, but either way, it doesn’t make any difference,” he said, “Whether it’s 60, 70, or 80% nobody’s ever heard of it. But it’s also 500, 600, 700, depending on the way you want to look at it, the way you word the calculation.”
Kennedy and Trump’s statements come as the administration has sought to promote its attempts to slash prescription drug prices. The Oval Office event on Thursday centered on a deal Trump had made with the biotech company Regeneron that involved drug price reductions for some Americans, along with tariff relief for the corporation.
This past February, the administration also launched the TrumpRx website, which it’s pitched as a way to help consumers purchase lower-cost drugs directly. The platform has been scrutinized, however, for the limited number of drugs on it and the fact that cheaper generic alternatives are available for many of these drugs elsewhere.