Continental Airlines Inc. (CAL) has emerged as the world's most influential carrier, according to a new equity index launched Wednesday by NYSE Euronext (NYX).

The Houston-based carrier, which brands itself as the "world's fifth largest," has the highest weighting in the 25-member index at 16.4%. It is ranked 12th by market value in the global airline sector.

The launch of the NYSE Arca Global Airline Index (AXGAL) highlights the enduring investor interest in the highly-volatile sector, whose fortunes have become closely allied to oil prices.

NYSE Arca said it was developed at the request of Claymore Advisors LLC as the backbone of an exchange-traded fund.

It is the first new index to be offered since the American Stock Exchange was acquired last year by NYSE Euronext.

"We hope it will be the first of many new indexes, we but can't put a number on that at this point," said George Patterson, head of index design.

Patterson said the airline index includes the largest and most liquid industry stocks, with "a modified equal-dollar weighting methodology to ensure that each component exposure is constrained for liquidity, size and domicile."

The result is an index weighted 70% towards U.S. carriers, which fill the first eight positions.

Singapore Airlines Ltd (C6L.SG), the world's largest carrier by market value, is relegated to ninth position, though at $9.1 billion is four times the size of Continental.

Southwest Airlines Inc. (LUV) is the largest U.S. airline by market value and ranks third in the index weighting after AMR Corp (AMR).

To be included in the index, airlines need to maintain a minimum market value of at least $100 million and a 100-day average daily trading volume not less than $500,000.

Patterson said the index components are checked quarterly to be sure they meet the index's rules. During the quarter, components can change only if the shares stop trading due to a merger or bankruptcy.

U.S. airline stocks continue to be tracked by the AMEX Airline Index (XAL), which includes shares of 13 carriers. This includes domestic operators and some overseas airlines that trade in the U.S. as American Depository Receipts.

"We hope the new index will be used as a proxy for global airlines, the same way XAL is used to follow U.S. airline stocks," Patterson said.

-By Ann Keeton; Dow Jones Newswires; 312-750-4120; ann.keeton@dowjones.com

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