WASHINGTON — Flights in the United States were more crowded than ever in 2007, running at 76 percent capacity compared with 60 percent 10 years earlier, according to a USA Today analysis of Transportation Department data.

Record-high fuel prices guarantee that trend will continue, analysts said.

"Don't expect load factors to go down," airport consultant Mike Boyd said. "Airlines are pulling back capacity because they can't make money at $110 (per barrel) oil. That's going to mean fewer discount seats and fewer open seats."

Airplane crowding has increased steadily since 2002 partly because more people are taking commercial flights — a record 769 million flew last year on U.S. airlines, up from 613 million five years ago.

At the same time, airlines are flying smaller airplanes. In 2002, the average flight had 106 seats, according to USA Today's analysis. In 2007, the average size was 94 seats, thanks to increased use of 50- and 70-seat regional jets.

"Airlines have cut back on capacity to drive up (fares)," said Stephen Van Beek, president of the Eno Transportation Foundation, a Washington, D.C., research group. "They're using smaller planes domestically and pushing bigger wide bodies to international flights."

Although federal figures show that the average airplane is nearly a quarter empty, Van Beek said that calculation includes flights at inconvenient times. "A lot of times you'll see late-night flights that have obscenely few people on them," Van Beek said.

For the typical passenger flying during the day, "flights are totally full," Boyd said.

Florida airports including Miami, West Palm Beach and Orlando have among the most-crowded flights. Southwest Florida International Airport in Fort Myers, one of the fastest-growing airports, had the most-congested flights of the 100 largest airports: 81 percent of the seats were filled on departing planes.