Hartsfield-Jackson International Airport is again the world's busiest, handling more than 104 million passengers last year, according to Atlanta Mayor Kasim Reed and airport officials.

Of the passengers, about 80 percent were flying on hub carrier Delta Air Lines or a Delta Connection carrier. About 9.7 percent were passengers on Southwest Airlines, the second-largest carrier at Hartsfield-Jackson.

About 2.8 percent flew on American, 2 percent on United, 1.8 percent on Spirit and 1.1 percent on Frontier. All other carriers made up less than 1 percent.

Last year, Hartsfield-Jackson officials had decided that the airport preferred to be known as "world's most traveled."

But after Reed announced the airport's repeat title this week during his State of the City address, the airport didn't shy away from the "world's busiest" phrase in its announcement of nearly 104.2 million passengers in 2016.

Hartsfield-Jackson also said it handled more flights than any other U.S. airport, with a total of 898,356 flights at Hartsfield-Jackson last year.