In fiscal year 2008, the Departmentof Interior's Minerals ManagementService (MMS) collected over $12billion in royalties from oil and gasproduction from federal lands andwaters. Companies that producethis oil and gas self-report to MMSdata on the amount of oil and gasthey produced and sold, the valueof this production, and the amountof royalties owed. Since 2004, GAOhas noted systemic problems withthese data and recommendedimprovements. GAO is providing:(1) a descriptive update on MMS'skey efforts to improve the accuracyof oil and gas royalty data; (2) ourassessment of the completenessand reasonableness of fiscal years2006 and 2007 oil and gas royaltydata-the latest data available; and(3) factors identified by oil and gascompanies that affect their abilityto accurately report royalties owedto the federal government.To prevent erroneous data frombeing entered into MMS databasesand to check the quality of dataalready entered,