NYMEX to change natgas basis, index swap margins

NEW YORK, March 6 (Reuters) - The New York Mercantile Exchange (NYMEX) said late Wednesday it will change margins for some of its natural gas basis and index swap futures contracts, effective at the close of business on Thursday.

Margins for the first month of the CIG Rockies basis swap futures contract will decrease to $1,200 from $1,500 for clearing members, to $1,320 from $1,650 for members, and to $1,620 from $2,025 for customers.

Margins for the second to sixth months will decrease to $1,200 from $1,500 for clearing members, to $1,320 from $1,650 for members, and to $1,620 from $2,025 for customers.

The margins for the seventh to ninth months will remain unchanged.

Margins for all other months will increase to $500 from $400 for clearing members, to $550 from $440 for members, and to $675 from $540 for customers.

The margins for the first month of the Alberta basis swap futures contract will decrease to $800 from $1,000 for clearing members, to $880 from $1,100 for members, and to $1,080 from $1,350 for customers.

Margins for the second to 12th months will remain the same.

The margins for all other months will increase to $300 from $200 for clearing members, to $330 from $220 for members, and to $405 from $270 for customers.

Margin changes for other natural gas basis and index swap contracts including Waha, Sumas and Northwest Pipeline can be found on the exchange Web site www.nymex.com. (Reporting by Joe Silha)