Photographer: Bing Guan/Bloomberg

U.S. mortgage rates dropped to a record low for the fourth time since the coronavirus began roiling financial markets earlier this year. They may not have much more room to fall.

The average for a 30-year fixed-rate loan was 3.13%, down from 3.21% last week and a low point in almost 50 years of data-keeping by Freddie Mac. The previous record was 3.15%, reached late last month.

Rates are sliding toward a theoretical floor for lenders who have to cover their fixed costs. They’ve tumbled as the Federal Reserve holds its benchmark rate near zero and buys mortgage bonds as part of its plan to stimulate the economy.

It’s plausible that 30-year rates could drop below 3%, possibly reaching 2.7% on average, said Tendayi Kapfidze, chief economist at LendingTree.

“In a practical sense, there’s probably not much room to go,” Kapfidze said. “Though we are in an unprecedented economic environment and there’s a theoretical possibility rates will fall further.”

Low rates have stimulated demand for homes. Applications for purchase loans climbed for a ninth straight week to the highest level since January 2009, the Mortgage Bankers Association said Wednesday.