ByJohn S. McClenahen Spurred by low interest rates, sales of existing, single-family homes in March increased 5.7% to a seasonally adjusted annual rate of 6.48 million units from February's revised figure of 6.13 million units, the Chicago-based National Association of Realtors (NAR) reported on April 27. March's sales rate was the second highest on record; the record is the 6.68 million rate recorded in September 2003. "The housing needs of a growing population timed nicely with historically low mortgage interest rates and a rebounding economy in March," says David Lereah, NAR's chief economist. "Although interest rates are rising modestly, an improving job market is creating a favorable backdrop for home sales, but at a somewhat slower pace in the months ahead," he expects. According to NAR's numbers, the median existing home price in the U.S. this March was $174,100, some 7.4% higher than the $162,100 median price in March 2003.