ByJohn S. McClenahen Strong sales of existing single-family homes in December helped produce an annual sales record in 2003, the Chicago-based National Association of Realtors (NAR) reported on Jan. 26. December sales were at a seasonally adjusted annual rate of 6.47 million, up from November's rate of 6.05 million. "We've been expecting the pace of home sales to ease, and a decline in November seemed to indicate a more sustainable pace, but the rebound in December -- the second highest monthly pace on record -- shows there's still a lot of life in this market," says David Lereah, NAR's chief economist. "The biggest factor is a resumed decline in mortgage interest rates, which have been much lower than most analysts expected." For all of 2003, existing homes sales totaled a record 6.1 million, nearly 10% higher than the previous record of 5.566 million in 2002. NAR has been keeping track of the numbers since 1968.