RAPID CITY - Airline traffic at Rapid City Regional Airport was up slightly in May, airport officials reported.

During the month, 40,712 people flew into or out of Rapid City, an increase of 0.8 percent over traffic in May 2006.

Year-to-date airline passenger traffic still lags behind the same period of 2006. Between January and May, 156,996 passengers have flown into or out of Rapid City Regional Airport. That's down about 2.1 percent.

Two other categories, freight traffic and total aircraft operations, were also higher in May. Freight traffic jumped 72 percent to 368,641 pounds. Total aircraft operations - the number of takeoffs and landings by commercial airlines, freight carriers and private aircraft - increased 1.4 percent to 4,055.

United Express was the airport's busiest carrier during May. The airline carried 17,570 passengers to the United Airlines hubs in Denver and Chicago. Northwest Airlines, with service to Minneapolis-St. Paul, carried 15,553 passengers. The Skywest/Delta Connection route to Delta Airlines' hub in Salt Lake City, carried 5,528 passengers. Allegiant Air's Las Vegas route carried 2,061 passengers.