After reaching a 19-month high, pending home sales eased in December but stayed above year-ago levels, according to the National Association of Realtors.

The Pending Home Sales Index, a forward-looking indicator based on contract signings, declined 3.5 percent to 96.6 in December from 100.1 in November but is 5.6 percent above December 2010 when it was 91.5. The data reflects contracts but not closings.

Lawrence Yun, NAR chief economist, said the trend line remains positive. “Even with a modest decline, the preceding two months of contract activity are the highest in the past four years outside of the homebuyer tax credit period,” he said. “Contract failures remain an issue, reported by one-third of Realtors® over the past few months, but home buyers are not giving up.”

Yun said some buyers successfully complete the sale after a contract delay, while others stay in the market after a contract failure and make another offer. “Housing affordability conditions are too good to pass up,” he said. “Our hope is lending conditions will gradually improve with sustained increases in closed existing-home sales.”

The PHSI in the Northeast declined 3.1 percent to 74.7 in December and is 0.8 percent below a year ago. In the Midwest the index rose 4.0 percent to 95.3 and is 13.3 percent higher than December 2010. Pending home sales in the South slipped 2.6 percent to an index of 101.1 in December but are 4.9 percent above a year ago. In the West the index fell 11.0 percent in December to 107.9 but is 3.7 percent higher than December 2010.