San Diego’s median housing price in September increased $7,000 above the median in the prior month to $422,000, according to Dataquick, the La Jolla real estate research firm.

Over the 12 months, the median house price here has increased 20.6 percent.

Home sales in September declined a bit to 3,383 from nearly 4,100 in August, but have risen 5.3 percent over the previous 12 months, the report said.

The results mirror the results for the Southern California housing market, which showed the region’s median price in September at $382,000, up 21 percent over the year. Sales in the six-county region for September were about 19,000, up 7 percent from the same month in 2012, but down from August’s total sales by 17 percent.

The August to September decline in house sales has held steady since 1988, Dataquick said.

As has been the case for much of the past several years, the number of houses in the middle and upper price ranges outpaced sales in lower-priced bracket.

Foreclosures have also consistently declined in recent years reflecting lenders’ reluctance to foreclose on properties. Last month the number of foreclosure sales made up only 6.3 percent of all resales in the region, which was the lowest since May 2007. In February 2009, foreclosures hit a high of nearly 57 percent of the region’s total sales.

Cash buyers still exert a big influence on the region’s market and accounted for nearly 28 percent of last month’s sales. But that was down from the same month one year ago when they made up 32 percent of the total.

Cash buyers paid a median of $335,000 last month, up 35.6 percent from the like period one year earlier.

— Mike Allen