Petroleum Development's 2007 Year-End Reserves Up at 686 Bcfe

Petroleum Development Corporation reported that independent reserve engineers from Ryder Scott and Wright & Company have completed estimates of the Company's YE2007 Proved Reserves, in accordance with SEC guidelines. Their estimate of proved reserves as of December 31, 2007 is 686 billion cubic feet equivalent (Bcfe, where 1 barrel of oil is equal to 6 thousand cubic feet equivalent), including 368 Bcfe of proved developed reserves and 318 Bcfe of proved undeveloped reserves. This compares to 323 Bcfe of total reserves reported at the end of 2006 (187 Bcfe proved developed and 136 Bcfe proved undeveloped).

"The doubling of PDC's estimated proved reserves from year-end 2006 is a result of effective integration of the acquisitions made early this year, in addition to organic growth from of our active drilling program," said Steven R. Williams, Chairman and CEO. "The Company's significant undeveloped reserve potential will form the foundation for continuing growth for the next 4-5 years."

In addition to proved reserves, the Company estimates that it has an additional 358 Bcfe of "probable" and "possible" reserves. In combination with the proved reserves, this brings the Company's total 3P reserves (proved, probable and possible) to more than one trillion cubic feet equivalent. The Company's probable and possible reserves consist primarily of undeveloped drilling locations and behind pipe reserves in active development areas in Wattenberg field, Grand Valley field, and the Northeast Colorado area. The SEC permits reporting of only proved reserves in filings. Probable and possible reserves are, by nature, more uncertain than estimates of proved reserves and as a result are subject to substantially greater risk of not actually being realized. Probable reserves are unproved reserves that the Company believes are more likely than not to be recoverable. Possible reserves are unproved reserves that are less likely to be recoverable than probable reserves.