DAYTON — Passenger traffic at Dayton International Airport declined by 1 percent in September from the same month in 2010, but the year-to-date total is up by nearly 2 percent from a year ago.

The total number of passengers boarding flights in Dayton was 106,784 in September, down from 107,912 in the same month a year earlier, the airport’s management reported. The airport’s total for 2011 through September was 955,064, an increase from last year’s 940,285 at this point.

Several airlines that are among the busiest in Dayton also reported declines in passenger traffic during September, but there were exceptions. American Airlines reported a 32 percent increase in September, to 13,310 from the prior year’s 10,050. Frontier Airlines carried 9,235 passengers during the month, a 4 percent increase from the prior 8,875.

Delta Air Lines, the Dayton airport’s busiest carrier, hauled 27,406 passengers in September, down by one-10th of 1 percent from the prior year’s 27,431.