text: • Mutineer-Exeter – a 
  
  disappointing appraisal and 
  development drilling campaign 
  resulted in downgrades in 1P 
  reserves of 10 million boe and 
  2P reserves of 13 million boe. 
  
  The average Proven reserve 
  replacement cost for 2004 was 
  US$12.37 per boe. Replacement 
  costs in any one year are affected 
  by the timing of spending and 
  reserve bookings, so a three-year 
  average is a more reliable 
  indicator of costs. Santos’ three- 
  year average replacement cost of 
  US$7.19 per boe is world- 
  competitive. 
  
  • John Brookes – integration of 
  
  the late 2003 drilling results in 
  the John Brookes gas field, 
  along with detailed reservoir 
  modelling, resulted in a 
  significant positive revision of 
  15 million boe of 1P and 32 
  million boe of 2P reserves. 
  
  • East Spar – disappointing 
  production performance 
  resulted in downgrades in 1P 
  reserves of 3 million boe and 
  2P reserves of 8 million boe. 
  2004 was also a significant year 
  in terms of development, with 
  some 102 million boe of 1P 