CONSOLIDATED STATEMENTS OF PROFIT OR LOSS AND OTHER COMPREHENSIVE INCOME  - 55 -  The accompanying notes are an integral part of these consolidated financial statements  For the year ended 31 December  Note  2014  US$’000 2013  US$’000  Oil and natural gas revenue  3   159,793 85,345  Lease operating and production tax expense  4  (20,489)  (18,383)  General and administrative expense  5  (15,527)  (15,297)  Depreciation and amortisation expense  16, 19  (85,584)  (36,225)  Impairment expense  17  (71,212)  -  Exploration expense  18  (10,934)  Finance costs  (699)  232  Gain on sale of non-current assets  6  48,604  7,335  Gain (loss) on derivative financial instruments  11,009  (554)  Other income  (481) (944)  Profit before income tax  14,480  21,509  Income tax benefit/(expense)  7  841  (5,567)  Profit attributable to owners of the Company  15,321  15,942  Other comprehensive income Items that may be reclassified subsequently to  profit or loss:  Exchange differences arising on translation  of foreign operations (no income tax effect)  684  (421)  Other comprehensive income (loss)  Total comprehensive income  attributable to owners of the Company  16,005 15,521 Earnings per share (cents) Basic earnings 10  2.9  3.9 Diluted earnings  2.9  3.8