(AXcess News) Washington – The National Association of Realtors said in its report Monday that there wasn’t enough inventory of available homes for sale in December to boost results,though pending home sales were still above year-ago levels of 6.9%.

“The supply limitation appears to be the main factor holding back contract signings in the past month,” said Lawrence Yun,NAR Chief Economist.

Yun went on to say that the market remains relatively strong,pointing out that contract activity has risen for 20 consecutive months.

Pending home sales in December fell 4.3 percent

Yun said shortages of available inventory are limiting sales in some areas. “Supplies of homes costing less than $100,000 are tight in much of the country,especially in the West,so first-time buyers have fewer options,” he said. “We expect a seasonal rise of inventory in the spring to help,but a seller’s market may be developing. Much of the West is already a seller’s market for homes priced under a million dollars,but conditions are much more balanced in the Northeast.”

Even with tighter inventory,a pent-up demand and favorable affordability conditions bode well for the market. Yun expects existing-home sales to increase another 9 percent in 2013,following a 9 percent rise in 2012.