Rate on 30-year fixed mortgage rises to 4.81 pct.

NEW YORK (AP) — The average rate on the 30-year fixed mortgage edged up this week as bond yields increased.

Freddie Mac said today the average rate rose to 4.81 percent this week from 4.80 percent the previous week. It hit a 40-year low of 4.17 percent in November.

The average rate on the 15-year loan slipped to 4.08 percent from 4.09 percent. It reached 3.57 percent in November, the lowest level on records starting in 1991.

Rates have been little changed this year after spiking more than half a percentage point in the last two months of 2010. Investors sold off Treasury bonds during that time, driving yields lower. Mortgage rates tend to track the yield on the 10-year Treasury note.

High foreclosures, job worries and expectations that home prices will fall further have kept many potential homebuyers on the sidelines. Historically low mortgage rates haven’t been enough to jumpstart the housing market.