Seattle-based Horizon Air, which handles the majority of the commercial air service at the Medford airport, reported a system-wide 3.9 percent increase in December traffic

The Alaska Air Group unit's capacity remained flat compared to December 2012, resulting in a 3.1-point increase in load factor for a December record of 82.5 percent.

Horizon also reported 78.5 percent of its flights arrived on time in December.