Freddie Mac released its weekly update on national mortgage rates this morning.

30-year fixed rate mortgages (FRM) inched up a single basis point, to 3.52%, while 15-year FRMs held steady at 2.76%. Among adjustable-rate mortgages, 5/1 ARMs rose two basis points, to 2.63%.

Only one-year ARMs moved the other way, declining one basis point, to 2.63%. But in all four cases, the movements this week were minimal.

Commenting on the numbers, Freddie Mac vice president and chief economist Frank Nothaft observed that the glacial changes in mortgage rates mirror the slow pace of GDP growth: "With gross domestic product growing only 0.1 percent in the fourth quarter of 2012, inflation remains at bay and consequently mortgage rates low. In fact, the price index of personal consumption expenditures rose only 0.1 percent in January which was below the market consensus forecast."

The good news is that "these low mortgage rates are helping to revive the housing market," said Nothaft. "The CoreLogic home price index rose 9.7 percent between January 2012 and 2013, marking the largest annual increase since April 2006."