For crude oil options, expiration months will be every month from June until December 2008, in addition to the June and December months from 2009 through 2015. The move to six-month expiration periods will be made to concentrate liquidity in the market. Natural gas options contracts will be available for 24 consecutive months starting in June.
The electronically traded gold and silver options will reflect their current cycles on the floor. The strike price intervals will be the same as the floor-traded options contracts.