Appalachia Fayetteville (in Bcfe) Northeast Southwest Shale  (1) Other  (2) Total December 31, 2015 2,319  611  3,281  4  6,215  Net revisions Price revisions (794) (127) (116) – (1,037) Performance and production revisions 318  199  163  3  683  Total net revisions (476) 72  47  3  (354) Extensions, discoveries and other additions Proved developed 81  157  19  – 257  Proved undeveloped – – 25  – 25  Total reserve additions 81  157  44  – 282  Production (350) (148) (375) (2) (875) Acquisition of reserves in place –  – – – – Disposition of reserves in place – (15) – – (15) December 31, 2016 1,574  677  2,997  5  5,253  Net revisions Price revisions 903  738  49  1  1,691  Performance and production revisions 154  125  358  4  641  Total net revisions 1,057  863  407  5  2,332  Extensions, discoveries and other additions Proved developed 790  419  48  1  1,258  Proved undeveloped 1,100  5,186  543  – 6,829  Total reserve additions 1,890  5,605  591  1  8,087  Production (395) (183) (316) (3) (897) Acquisition of reserves in place – – – – – Disposition of reserves in place – – – – – December 31, 2017 4,126  6,962  3,679  8  14,775  Net revisions Price revisions 41  106  6  1  154  Performance and production revisions 107  272  (6) (1) 372  Total net revisions 148  378  – – 526  Extensions, discoveries and other additions Proved developed 154  22  1  – 177  Proved undeveloped 397  435  – – 832  Total reserve additions 551  457  1  – 1,009  Production (459) (243) (243) (1) (946) Acquisition of reserves in place – – – – – Disposition of reserves in place – – (3,437) (6) (3,443) December 31, 2018 4,366  7,554  – 1  11,921  (1) The Fayetteville Shale E&P assets and associated reserves were divested December 3, 2018. (2) Other includes properties outside of the Appalachian Basin and Fayetteville Shale. The Company's December 31, 2018 proved reserves included 190 Bcfe of proved undeveloped reserves from 30 locations that had a positive present value on an undiscounted basis in compliance with proved reserve requirements, but do not have a positive present value when discounted at 10%. These properties had a negative present value of $24 million when discounted at 10%. The Company made a final investment decision and is committed to developing these reserves within the next five years from the date of initial booking.  The Company's December 31, 2017 proved reserves included 1,375 Bcfe of proved undeveloped reserves from 330 locations that had a positive present value on an undiscounted basis in compliance with proved reserve requirements, but that have a negative $124 million present value when discounted at 10%. The Company's December 31, 2016 proved reserves included 77 Bcfe of proved undeveloped reserves from 15 locations that had a positive present value on an undiscounted basis in compliance with proved reserve requirements, but that have a negative $11 million present value when discounted at 10%. 130 The following table summarizes the changes in reserves for 2016, 2017 and 2018: Table of Contents Index to Financial Statements