Passenger activity at Des Moines International Airport was up 8.1 percent in September compared with the same month a year ago. A total of 176,482 passengers flew out of or into the airport, compared with 163,254 in September 2012. Year to date, passenger activity is up 6.4 percent from last year's record-breaking pace. Cargo activity was down 8.7 percent for the month and 4.1 percent for the year.