Arena Resources, Inc. (Arena) is engaged in the acquisition, exploration and development of oil and gas properties, and the production and sale of oil and gas. The Company owns interests in oil and gas properties located in Oklahoma, Texas, Kansas and New Mexico. The Company has a portfolio of oil and natural gas reserves, with approximately 85% of its proved reserves consisting of oil and approximately 15% consisting of natural gas. Approximately 31% of Arena's proved reserves are classified as proved developed producing (PDP); approximately 7% of its proved reserves are classified as proved developed non-producing (PDNP), and approximately 62% are classified as proved undeveloped (PUD). The Company sells its oil and natural gas production to end users, marketers and other purchasers who have access to nearby pipeline facilities. During the year ended December 31, 2008, the Company completed the drilling of 233 wells.