The investment seeks to reflect the daily changes in percentage terms of the price of natural gas delivered at the Henry Hub, Louisiana, as measured by the daily changes in the average of the prices of specified short-term futures contracts on natural gas. The Benchmark Futures Contracts are the futures contracts on natural gas as traded on the New York Mercantile Exchange (the NYMEX?) that are the near month contract to expire and the contracts for the following 11 months, for a total of 12 consecutive months? contracts, except when the near month contract is within two weeks of expiration.