On October 31, 2013, the Company completed the acquisition of certain oil and natural gas properties located in the Permian Basin for total consideration of approximately $528 million. The acquisition included approximately 175 Bcfe of proved reserves as of the acquisition date.
During 2013, LINN completed other smaller acquisitions of oil and natural gas properties located in various operating regions. The Company, in the aggregate, paid approximately $40 million in total consideration for these properties.
On May 31, 2013, LINN, through one of its wholly owned subsidiaries, together with the Company's partners, Panther Energy, LLC and Red Willow Mid-Continent, LLC, completed the sale of its interests in certain oil and natural gas properties located in the Mid-Continent region to Midstates Petroleum Company, Inc. Proceeds received for LINN's portion of its interests in the properties were approximately $218 million, net of costs to sell of approximately $2 million. LINN used the net proceeds from the sale to repay borrowings under its Credit Facility.
LINN increased year-end 2013 proved reserves by 34 percent compared to year-end 2012 reserves. As of December 31, 2013, the Company's estimated proved reserves were 6.4 Tcfe, of which approximately 34 percent were oil, 47 percent were natural gas and 19 percent were NGL. Approximately 68 percent were classified as proved developed, with a total standardized measure of discounted future net cash flows of $11.9 billion. The Company's estimated reserves at year-end 2013 were based on the average first-day-of-the-month prices for each month, which were $96.89 per Bbl and $3.67 per MMBtu.
During 2013, LINN spent approximately $1.17 billion on its oil and natural gas capital program, drilling 559 gross wells and completing numerous workover and recompletion projects. The Company demonstrated its ability to grow organically through the addition of 527 Bcfe of proved reserves, primarily as a result of the Mid-Continent, Green River, Hugoton and Williston Basin drilling programs. The Company generated cost-to-add reserves of approximately $2.21 per Mcfe from extensions, discoveries and other additions during 2013. LINN recorded 100 Bcfe of negative performance revisions in 2013. This revision included the removal of approximately 300 Bcfe comprised of mostly proved undeveloped reserves associated with the Granite Wash, partially offset by an increase of approximately 200 Bcfe comprised of mostly proved developed reserves associated with the Company's Hugoton and Green River assets.