Des Moines International Airport had a 5 percent increase in passenger traffic in 2016 over the previous year, according to figures released Tuesday by the Des Moines Airport Authority. More than 2.48 million passengers enplaned and deplaned at the airport last year, up from 2.37 million in 2015. Passenger traffic for the month of December 2016 was up 2.8 percent from the year-ago period. Frontier Airlines had the biggest percentage growth in passengers in 2016, up 37 percent from 2015. The three airlines with the largest passenger market share for the airport in 2016 were American, United and Delta, with market shares of 29, 25 and 22 percent, respectively.