Fixed mortgage rates rise, adjustable rates fall Long-term fixed mortgage rates return to January levels; average adjustable-rate mortgage rates slightly lower than earlier this year, says Freddie Mac. February 21 2008: 11:02 AM EST NEW YORK (CNNMoney.com) -- Adjustable-rate mortgages could become more popular as the difference between long-term fixed rates and adjustable rates increases, Freddie Mac reported Thursday.

"After trending up in the past two weeks, long-term fixed mortgage rates are back up to nearly where they were at the beginning of the year. In contrast, average rates on adjustable-rate mortgages are about 0.5 percentage points below levels of the first week of this year," said Freddie Mac (FRE, Fortune 500) vice president and chief economist Frank Nothaft in statement Thursday.

"As the spread between long-term fixed-rates and adjustable-rates widens, it's possible we could see a slight increase in the popularity of adjustable-rate mortgages," Nothaft noted.

The government-sponsored loan buyer said 30-year fixed-rate loans averaged 6.04% for the week ending Thursday, up from 5.72% last week.

Last year at this time, the 30-year rate averaged 6.22%, Freddie Mac said.

Freddie Mac also said 15-year fixed-rate loans averaged 5.64%, up from 5.25% last week. A year ago, the 15-year rate averaged 5.97%.

Rates on five-year adjustable-rate mortgages (ARMs) averaged 5.37%, up from 5.19% last week. A year ago, the 5-year rate averaged 5.96%.

One-year Treasury-indexed ARMs averaged 4.98%, down from 5% last week. At this time a year ago, the 1-year ARM averaged 5.49%.