Average interest rates on long-term U.S. home loans increased by the fastest pace in over twenty years during the latest week, according to mortgage giant Freddie Mac Thursday.

The company reported that 30-year fixed-rate mortgages carried an average rate of 6.46 percent, excluding fees during the week ended Oct. 16, a growth of 52 basis points from 5.94 percent the week before. That represents the largest weekly increase since the middle of April 1987. The current rate is even up from last year at this time when the rate was 6.40 percent.

The average rate on 15-year fixed rate loans rose to 6.14 percent during the previous week, from 5.63 percent. One year ago, the average was 6.08 percent.

One-year adjustable rate mortgages (ARMs) saw little change, however, as the average rate inched up to 5.16 percent from 5.15 percent a week earlier. Last year, the average rate was 5.76 percent.

“Interest rates for 30-year fixed-rate mortgages rose this week to an 8-week high,” said Frank Nothaft, Freddie Mac vice president and chief economist. “ARM rates, which tend to be based on shorter-term benchmarks, showed smaller gains in part due to the Federal Reserve’s October 8 inter-meeting rate cut in the overnight lending rate.

“Recent economic reports suggest the economy is still slowing. For instance, retail sales fell for the third consecutive month by 1.2 percent in September. In addition, in its latest Beige Book, released October 15th, the Federal Reserve indicated that economic activity weakened in September across all twelve Federal Reserve Districts and that several Districts also noted that their contacts had become more pessimistic about the economic outlook.”

On a regional level, average rates on 30-year mortgages were highest in the Southeast at 6.51 percent, excluding fees, and lowest in the West at 6.37 percent.