After going into free-fall for much of 2012, fixed mortgage rates started off 2013 with very slight declines, according to Freddie Mac’s Primary Mortgage Market Survey.

The average 30-year fixed rate was 3.34 percent (0.7 point) for the week ending January 3, down from 3.35 percent in the last week of 2012. The average 30-year fixed rate was 3.91 percent at the beginning of last year.

The 15-year fixed average also fell, sliding to 2.64 percent (0.7 point) from 2.65 percent previously. A year ago at this time, the 15-year fixed rate averaged 3.23 percent.

Meanwhile, adjustable rates inched up. The 5-year Treasury-indexed hybrid adjustable-rate mortgage (ARM) averaged 2.71 percent (0.6 point) this week, up from 2.70 percent in the last survey. The 1-year ARM averaged 2.57 percent (0.4 point), up from 2.56 percent. At the start of 2012, the 5-year and 1-year ARMs averaged 2.86 percent and 2.80 percent, respectively.

Bankrate’s weekly survey also showed negligible changes across the board, with the 30-year fixed average falling one basis point to 3.58 percent and the 15-year fixed average inching up the same amount to 2.88 percent. The 5/1 ARM was similarly flat, slipping one basis point to 2.76 percent.

While Washington may have avoided a disaster in reaching an agreement on the budget, that’s not likely to cause a long-term upward trend, Bankrate said in a release.

“Relief that the fiscal cliff has been averted will likely send mortgage rates higher in the next week or so, but don’t take this as the beginning of a long-standing trend,” Bankrate said. “We still have a slow growth economy with high unemployment, and the debt ceiling negotiations will get started soon and are sure to be contentious. This will only serve to fuel uncertainty and volatility, both of which may end up bringing mortgage rates back down.”