A new study by Airlines Reporting Corp. (ARC) charts that air ticket purchases made through U.S. travel agencies for flights to ski destinations are on the rise.

ARC reported that overall ticket purchases for November 2016 through March 2017 are up nearly nine percent versus the same period in 2015-2016. The analysis was produced using ARC’s Global Agency Pro — an online business tool that tracks worldwide travel agency air ticket sales.

Travel booked through U.S. travel agents to smaller airports — those with fewer than 20,000 passengers per month — has grown more than six percent compared to 2015 and 5.8 percent for just December 2016. Travel to ski destinations in December 2016 alone has grown nearly 10 percent. Air travel booked to the smaller airports near ski destinations for December alone has also increased by 5.8 percent.

The top 15 ski destinations based on December growth include Gunnison, CO (21.6 percent), Hailey-Sun Valley, ID (17 percent), Vancouver, B.C. (12.3 percent), Jackson Hole, WY (12.1 percent), Denver, CO (11.6 percent) and Salt Lake City, UT (10 percent).