Global airline seat-occupancy levels fell the most in more than three years last month, hurt by an economic slowdown in the United States, the International Air Transport Association said.

Average seat occupancy, otherwise known as load factor, declined 0.6 percentage point in February from a year earlier to 73.3 percent, the industry group said in a statement today. That's the most since a 0.9 point drop in December 2004.

"Load factors tell the story," IATA Chief Executive Officer Giovanni Bisignani said in the statement. "They fell in the four largest carrier regions, showing the growing impact of the U.S. economic slowdown on the airline industry."

Northwest Airlines' February load factor rose 0.2 percentage points, to 81.1 percent.

High oil prices and dwindling demand for travel as economies falter following the U.S. credit crisis and decline in home values may shatter airline-industry earnings this year. IATA in December said profit will amount to about $5 billion, down from an earlier estimate of $9.6 billion and 11 percent lower than the 2007 figure. The Geneva-based association plans to update its guidance next month.

February seat occupancy suffered because the 9.2 percent gain in global passenger traffic lagged behind a 10.1 percent increase in capacity, IATA said.

Stock indexes in the United States, Europe and Asia have slumped this year amid mounting speculation that the world economy is slowing and company defaults will rise.

The price of crude oil has risen 61 percent in the past 12 months. Jet fuel now represents 28 percent of industry operating costs, compared with 13 percent at the beginning of the decade.

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