Virgin America is the top airline for the third year in a row, according to the Airline Quality Report, USA Today reports.

The AQR is in its 25th year. It analyzes the performance of U.S. carriers and it is a joint project of Wichita State and the Arizona campus of Embry-Riddle Aeronautical University. The authors of the report call it "the nation's longest running study of airline performance quality." 

Taking second place and moving up one place from 2013 was Hawaiian Airlines. Delta moved up from No. 4 to No. 3 and Jet Blue dropped into fourth place from second place in 2013. The fifth best airline, according to the report was Alaska Airlines, which also took fifth in 2013.

The overall airline industry declined from 2013, which was considered the "best-ever year in overall performance." The AQR noted that only three of 12 U.S. airlines actually improved in 2014, one held steady and eight declined.

The AQR study utilizes four "core elements" to calculate ratings. Things like whether the plane is on time, if people are denied boardings involuntarily, whether baggage is handled properly and customers' complaints go into consideration.

The ratings report connected the overall weak performance in 2014 to recent airline mergers. The report suggests that "airlines still have work to do to compete for customer loyalty." 

"Bigger isn't always better, and the downturn in performance suggests that customer perceptions of poor outcomes are warranted," said Dean Headley, associate professor of marketing at Wichita State's W. Frank Barton School of Business, in the report.

The AQR studied 12 airlines that carry at least 1 percent of passengers nationwide. Because of mergers, that number is down from 15 airlines last year. Now, four of the U.S. airlines carry 70 percent of the nation's passenger traffic.

Virgin, Hawaiian and Alaska were the only American airlines that managed to improve. SkyWest's service remained steady.

Virgin had success in keeping passengers on its planes. Only 0.09 times out of 10,000 passengers is a passenger denied boarding. The industry average is 1 out of 10,000 passengers. Headley says Virgin's average was "extremely low."

"They let people on the airplane -- they don't mess around," Headley said. "That generates a very good baggage handling rate. It's very low -- one of the lowest in the industry. And they don't have that many complaints." 

Delta, which took third in the AQR, was the only big carrier to appear in the top four. Experts say that Delta's merger with Northwest in 2010 has led to its improvement. United has struggled with its customer service after its 2010 merger with Continental. 

"The big difference is management of the airline really demanding the customer service," added study co-researcher Brent Bowen, dean of College of Aviation at Embry-Riddle Aeronautical University-Prescott. "Performance by the airlines is slipping while they claimed this would make them better." 

Which is your favorite airline? Leave a comment below and let us know what you think.