NEW YORK, N.Y., September 8, 2005 —The New York Mercantile Exchange, Inc., announced today that it will introduce three additional natural gas basis futures contracts on its NYMEX ClearPort^sm electronic trading and clearing platform beginning on September 11 for the September 12 trade date.

The futures contracts are based on the differential between the prices reported by Platts Inside FERC Gas Market Report and the Exchange floor-traded natural gas futures contract. The new contracts and their trading symbols are: Sonat basis futures (SZ), FGT Zone 3 basis futures, and Transco Zone 4 basis futures.

The contract units will be 2,500 million British thermal units (mmBtu), and the minimum price fluctuation will be $0.0025 per mmBtu. Contracts will be listed for 36 consecutive months, beginning with the October 2005 contract.

Fees for transactions submitted for clearing on NYMEX ClearPort^sm will be $0.54 per contract for members and $0.67 for non–members. For trading on NYMEX ClearPort^sm , liquidity providers will receive $0.25 per contract, and the participant on the other side of the trade will pay an all–inclusive fee of $0.65. Fees for cash settlement will be $0.54 for members and $0.67 for non–members.

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