CoMpAnY InteRest hIstoRIC FD&A Costs (1) RESERvES RECOnCILIATIOn – COMPAnY InTEREST (1) (1) Additional information on reserves is available in the Annual information form and in the february 10, 2011 news release titled “Arc  resources ltd. 2010 year-end reserves increase by 29 per cent”. 27 ARC ResouRCes AnnuAl  report 10 (1) Additional information on reserves is available in the Annual information form and in the february 10, 2011 news release titled “Arc  resources ltd. 2010 y ear-end reserves increase by 29 per cent”. 2010 2009 2008 2007 2006 proved reserves: Annual FD&A excluding FDC  $13.31 $10.48 $14.22 $20.37 $24.51 Three year average FD&A excluding FDC  $12.76 $13.76 $18.28 $18.51 $17.77 Annual FD&A including FDC  $18.15 $14.29 $21.87 $20.37 $27.53 Three year average FD&A including FDC  $17.96 $18.27 $22.85 $20.30 $20.31 proved plus probable reserves: Annual FD&A excluding FDC  $9.21 $6.44 $10.13 $19.00 $22.41 Three Year Average FD&A excluding FDC  $8.60 $9.57 $14.70 $16.57 $15.59 Annual FD&A including FDC  $14.23 $11.56 $17.00 $20.03 $27.20 Three Year Average FD&A including FDC  $14.05 $14.75 $19.84 $19.19 $18.99 ligHt And  HeAVy totAl  nAturAl oil MediuM crude  crude oil  crude  ngls  gAs equiVAlent   (mbbl)  (mbbl) (mbbl)  (mbbl)   (mmcf) (MBoe) proVed plus proBABle opening Balance 134,571  3,027  137,598  15,815  1,353,245  378,953 Exploration Discoveries  0  0  0  13  2,678  459 Drilling Extensions  6,329  40  6,369  940  120,192  27,341 Improved Recovery  631  6  637  27  1,098  847 Infill Drilling  4,469  56  4,525  2,627  214,018  42,822 Technical Revisions  847  139  986  1,311  126,866  23,441 Acquisitions  514  0  514  7,681  215,862  44,172 Dispositions  -4  0  -4  0  -28  -9 Economic Factors  -693  81  -612  -345  -15,959  -3,617 Production  -9,600  -379  -9,979  -1,549  -92,785  -26,992 closing Balance  137,063  2,970  140,033  26,520  1,925,187  487,418