News Release

Exchange Announces Margins for New Electricity Contracts

Thu Aug 11 2005

NEW YORK, N.Y., August 11, 2005 — The New York Mercantile Exchange, Inc., today announced margins for the eight new electricity contracts that will begin trading on NYMEX ClearPort® on August 14 for the August 15 trading session.

Margins for all months of the Cinergy hub off–peak swap futures, Michigan hub off–peak swap futures, and MISO Illinois off–peak swap futures contracts will be $2,500 for clearing members, $2,750 for members, and $3,375 for customers. Margins for all months of the Michigan hub calendar–month swap futures contract will be $3,000 for clearing members, $3,300 for members, and $4,050 for customers. Margins for all months of the Cinergy hub calendar–month swap futures, MISO Illinois hub calendar–month swap futures, and Minnesota hub calendar–month swap futures contracts will be $3,500 for clearing members, $3,850 for members, and $4,725 for customers. Margins for all months of the Minnesota off–peak swap futures contract will be $4,500 for clearing members, $4,950 for members, and $6,075 for customers.

Intra–commodity spread margin rates for the MISO Illinois off–peak swap futures contract will be $1,000 for clearing members, $1,100 for members, and $1,350 for customers. Intra–commodity spread margin rates for the Michigan hub calendar month swap futures and the MISO Illinois hub calendar–month swap futures contracts will be $1,200 for clearing members, $1,320 for members, and $1,620 for customers. Intra–commodity spread margin rates for the Cinergy hub off-peak swap futures and Michigan hub off–peak swap futures contracts will be $1,500 for clearing members, $1,650 for members, and $2,025 for customers. Intra–commodity spread margin rates for the Minnesota hub calendar–month swap futures contract will be $1,800 for clearing members, $1,980 for members, and $2,430 for customers. Intra–commodity spread margin rates for the Cinergy hub calendar–month swap futures contract will be $2,000 for clearing members, $2,200 for members, and $2,700 for customers. Intra–commodity spread margin rates for the Minnesota off–peak swap futures contract will be $2,500 for clearing members, $2,750 for members, and $3,375 for customers.

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