The average rate for 30-year fixed loans dropped to 4.27 percent, mortgage buyer Freddie Mac said Thursday. That's the lowest on records dating back to 1971, and down from 4.32 percent the previous week.
The average rate on 15-year fixed loans, a popular choice for refinancing, dropped to 3.72 percent from 3.75 percent. That was lowest on records dating back to 1991.
Rates have mostly fallen since spring as investors shifted money into the safety of Treasury bonds, lowering their yield. Mortgage rates tend to track those yields.