The number of passengers getting on and off planes at Des Moines International Airport was up 2.1 percent in October compared with the same month last year. Year to date, traffic is up 5.4 percent compared with the same period last year. Enplanements — the number getting on planes at the airport — were up 1.4 percent for October and 5.1 percent for the year. The airport is hoping for 2.5 percent annual growth in passengers to support a proposed new terminal building. The biggest gainer among the airlines in October was Allegiant at 23.1 percent. American Airlines carried the most passengers, and was up 1.8 percent for the month. Cargo was down 7.9 percent in October but is up 1.4 percent for the year.