More Americans purchased homes in December, yet total sales slipped in 2014 as first-time buyers struggled to find houses.

The National Association of Realtors says sales of existing homes rose 2.4 percent last month to a seasonally adjusted annual rate of 5.04 million. But over the course of the entire year, sales fell 3.1 percent to 4.93 million.

Only 29 percent of sales went to first-time buyers last month, compared to a historic average of 40 percent. Prospective buyers were priced out of the market due to rising home values and relatively stagnant incomes. Still, affordability has improved in recent months as mortgage rates have plunged, leading to the possibility of stronger sales in 2015.

Median home prices increased 6 percent over the past 12 months to $209,500.