The average rate on a 30-year fixed mortgage has hit a record low of 3.29%, driven down by investors shifting money into the safety of U.S. Treasurys as the viral outbreak deepens.

Mortgage buyer Freddie Mac says the average rate on the benchmark 30-year loan this week tumbled from 3.45% last week. The new rate is the lowest level since Freddie Mac started tracking it in 1971, the company says.

The steep decline came in a week when the Federal Reserve made a surprise emergency cut in its benchmark interest rate to support the economy in the face of the spreading coronavirus.