Aided by housing affordability, mortgage rates took a slide across the board for the week ending August 6, according to mortgage giant Freddie Mac (FRE). The average rate for 30-year fixed-rate mortgage (FRM) registered at 5.22% with an average 0.6 point, dropping from last week when it averaged 5.25% and 6.52% from last year. The 15-year FRM this week averaged 4.63% with a 0.6 point, declining from 4.69% a week ago and 6.10% from the same week last year. The Five-year Treasury-indexed hybrid adjustable-rate mortgages (ARMs) averaged 4.73% with 0.6 point, slipping from 4.75% last week and 6.05% last year. One-year Treasury-indexed ARMs averaged 4.78% with 0.5 point, a drop from last week’s average of 4.80% and 5.22% this week a year ago. “Better-than-expected economic reports helped to keep mortgage rates low this week,” said Frank Nothaft, Freddie Mac vice president and chief economist, in the weekly report. A separate survey from Bankrate.com showed that mortgage rates made modest increases from last week. The benchmark 30-year FRM rose to 5.65% from 5.59% four weeks ago but remained submerged from 6.74% last year. The 15-year FRM average rate jumped to 4.97%, and the rates for five-year ARMs grew to 5.03%. Write to Jon Prior.