Median sales prices inched up from May in the Portland area despite home sales lingering at a 15-year low in June. The median sales price for all house types rose 2.1% from May to $247,960, nearly 13% below the year-ago median price in the Portland-Vancouver-Beaverton, OR-WA metro area, according to a survey by MDA DataQuick. The real estate information service, which tracks trends nationally, saw 3,088 new and resale houses and condos close escrow during June, up 25.3% from May but still 5.8% below the year-ago level. It marked the 40th consecutive month of year-on-year decline in total sales, although single-family house re-sales inched up 0.5% from last year, marking the first year-on-year gain in that category since February 2006. New home sales came in 32% below the year-ago level, at 424 units sold in June. DataQuick noted that foreclosure resales represented lower share of resales in the month — 16.4% of all Portland area re-sales in June, down from 17.2% in May — which also relieved some of the downward pressure on prices. Sales in the mid-to-high price ranges picked up a bit as more traditional buyers became active in the market. “The latter is a seasonal norm reflecting buyers, including move-up buyers, purchasing because of a job change or to find a bigger house or one situated in a more desirable area,” DataQuick said in the survey. Write to Diana Golobay.