NEW YORK (CNN/Money) - Mortgage rates edged mostly lower for the week ended June 1, with the average 30-year fixed rate mortgage retreating to 6.57 percent from 6.61 percent a week earlier.

Rates ranged from 5.56 percent on the low end to 6.57 percent for the week, according to Informa Research Services. Looking back, rates climbed steadily during the first two weeks of May before leveling off at 6.61 percent by May 18.

The average 15-year fixed mortgage rate pulled back slightly to an average of 5.79 percent, down from 5.81 percent the previous week, with a range of 4.69 percent to 6.99 percent. Rates also climbed higher in the early part of May before slipping last week.

"The slight decline in 15-year and 30-year fixed rate mortgages is largely due to stronger bond prices," said Mavel Vargas, manager of mortgage lending research at Informa.

"Typically, when bond yields drop mortgage rates follow because lenders use the yields as benchmarks to set values on mortgages packaged and sold as securities."

Weekly rates information • 12-mo. CDs creep higher • Mortgage rates seep mostly lower • Credit card rates show no change

Adjustable rate mortgages (ARMs), however, remained unchanged from last week at 4.55 percent. ARM rates climbed steadily from 4.27 percent to 4.55 percent over the past month.

"Short-term interest rates, which drive the rates on ARMs, are holding steady but are higher than long-term interest rates, which drive fixed-rate loans," Vargas added.

"The difference between ARMs and fixed rates, and the risk of eventual upward ARM adjustments, makes fixed rate mortgages a good choice for many buyers."

Below are the rates for three key mortgage products from five top national mortgage lenders. You can compare rates from more institutions with the rate-search tools above.

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