Interest rates on 30-year and 15-year mortgages fell for the second consecutive week, offering encouraging news for people in the market to buy a home.

Freddie Mac said Thursday in its weekly nationwide survey that rates on benchmark 30-year fixed-rate mortgages declined this week to 6.21 percent, compared with 6.25 percent last week. Thirty-year mortgage rates hit a low this year of 5.38 percent in the week ended March 18.

Rates for 15-year, fixed-rate mortgages were 5.62 percent, down from 5.64 percent last week. Rates on one-year adjustable-rate mortgages this week rose to 4.19 percent from 4.13 percent.

A year ago, rates on 30-year mortgages averaged 5.24 percent, 15-year mortgages were at 4.63 percent and rates on one-year ARMs stood at 3.45 percent.

The Federal Reserve on Wednesday raised a key short-term interest rate to 1.25 percent from 1 percent, a 46-year low. The increase was the first in four years.

Although the Fed's action indirectly can influence rates on 30-year and 15-year mortgages, it has a direct effect on short-term one-year ARMs.

"As expected, long-term mortgage rates were relatively unaffected by the Fed's recent action," said Frank Nothaft, Freddie Mac's chief economist. Short-term rates, as expected, moved higher in response to the central bank's decision, he said.

The averages for mortgage rates do not include add-on fees known as points. Thirty-year and 15-year loans each carried an average fee of 0.6 point this week, while one-year ARMs carried an average fee of 0.7 point.

In a separate report, refinancings accounted for 33.4 percent of total mortgage loan applications filed last week, unchanged from the previous week, the Mortgage Bankers Association said.

EVENTS . . . The National Building Museum at 401 F St. NW in Washington plans a lecture, "Mount Joy, Pennsylvania: Small Town Main Street With a Smart-Growth Future," at 12:30 p.m. Thursday. Terry Kauffman, borough manager for Mount Joy, is to discuss how a small town can achieve economic development and community goals through smart-growth strategies. Admission is free. On Thursday from 8 p.m. to 9:30 p.m., the National Building Museum series Spotlight on Design is to feature "Sasaki Associates: Designing the Civic Realm." The program is about how Hideo Sasaki began his planning and landscape architecture practice more than 50 years ago with a basic set of beliefs: respect for the larger context; appreciation for simplicity, restraint, proportion and permanence; and a belief in collaborative practice. Dennis Pieprz, president of Sasaki Associates, is to discuss how those tenets are being followed through international architectural, urban and landscape projects. Admission is $17 ($12 for museum members, $10 for students); prepaid registration is required. For information call 202-272-2448; Web site: www.nbm.org.

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