A measure of the number of Americans who signed contracts to buy homes rose in January from December to the highest level in more than 2½ years. The increase suggests sales of previously occupied homes will continue rising in the coming months.

The National Association of Realtors said Wednesday that its seasonally adjusted index for pending home sales rose 4.5 percent last month to 105.9. That’s the highest since April 2010, when a homebuyer’s tax credit was about to expire.