This excerpt taken from the MRO 10-K filed Feb 29, 2008.
Average Production Costs (a)
(per barrel of oil equivalent)
Computed using production costs, excluding transportation costs, as disclosed in the Results of Operations for Oil and
Gas Producing Activities and as defined by the Securities and Exchange Commission. Natural gas volumes were converted to barrels of oil equivalent using a conversion factor of six mcf of natural gas to one barrel of oil.
Bet you've never seen portfolio analytics like these.