PULLMAN, Wash. — Low mortgage rates and home purchase contracts signed before the Sept. 11 terrorist attacks on the nation kept Washington’s housing market robust during the third quarter, according to the latest report from the Washington Center for Real Estate Research at Washington State University.

While the sales rate for existing homes backed off slightly from the second quarter record, the center estimates that 34,200 homes sold between July and September — still roughly 5 percent more than for the same period last year.

“This strength, in the face of signs of economic weakness even before the attacks, is an indication of the desire of most Washington households to own their own home,” said Glenn Crellin, center director. The center is part of the WSU College of Business and Economics and has produced quarterly statistics in conjunction with the Washington Association of Realtors since 1994.

“Of the 10 counties which reported year-to-year declines, only King and Pierce were in urban areas,” added Cheryl Ferrier, a Bellingham real estate agent and 2001 president of the association. “The greater Seattle market has been so strong that even a small drop still represents a very active market.”

Meanwhile, housing construction — which often leads into a slowdown — was somewhat weaker, with building permits statewide off by about 7 percent. “However, permits to build single-family homes were marginally higher,” Crellin noted. “All the slowdown was in apartment construction.”

Home prices increased at roughly the inflation rate, reaching a median price of $183,200, 3.6 percent above last year. The highest median price — $268,000 — was reported in King County, while the lowest median — $75,000 — was in Pacific County.

Although mortgage rates declined and incomes increased, the increase in prices resulted in a Housing Affordability Index of 123.2 — a little below the second quarter of 2001, but much more affordable than a year ago. This index rating means that a median income family (two or more persons related by blood, marriage or adoption) could afford to purchase a median price home using a 30-year mortgage at prevailing interest rates provided the family had access to a 20 percent down payment, and would have a 23 percent income cushion allowing the purchase of a more expensive home, a reduced down payment or an easier time making the payments. Even with this good news, a typical family in Jefferson, San Juan and Wahkiakum counties would not have been able to afford a median price home.

“Affordability conditions improved compared to last year and last quarter for first-time buyers,” said Crellin. While the typical renter household still cannot afford the typical starter home in most counties, they were inching closer before the recession began to intensify. Statewide incomes of would-be first time buyers are about 25 percent lower than required to qualify for a mortgage on the assumed starter home, priced at 85 percent of area median. By purchasing a slightly less expensive home or increasing the down payment a little, the typical first-time buyer could have purchased a home in nine counties where the first-time buyer index exceeded 90.

The center and the association time each quarterly release to coincide with national news releases on existing home sales by state and median home prices by metropolitan areas from the National Association of Realtors. Sales data is available for every county and median home prices and affordability are reported for 34 of Washington’s 39 counties. Those statistics are available as a snapshot on-line at www.cbe.wsu.edu/~wcrer, the address for the center Web site.