Reserves/Production Indices

Net proved reserves, Net probable reserves

MM boe

Years ended March 31 Net proved reserves Net probable reserves Net production (Thousand boe/day)
2015 2,434 1,610 408
2016 3,264 1,705 514
2017 3,304 1,389 521
2018 3,857 1,443 450
2019 4,010 1,202 424

Reserves to production ratio (Proved reserves, Proved reserves + Probable reserves)

(Years)

Years

Years ended March 31 Reserves to production ratio
Proved reserves Proved reserves + Probable reserves
2015 16.4 27.2
2016 17.4 26.4
2017 17.4 24.7
2018 23.5 32.4
2019 25.9 33.7

Reserve replacement ratio (3-year average)

(%)
Years ended March 31 Reserve replacement ratio
(3-year average)
2015 100
2016 321
2017 246
2018 362
2019 246

Average expenses per boe produced (Production cost, Selling general and administrative expenses)

(U.S.$)

U.S.$

Years ended March 31 Average expenses per boe produced (US$)
Production cost Production cost (Excluding royalty) Selling general and administrative expenses
2015 17.8 11.2 3.5
2016 12.6 7.8 2.6
2017 11.2 6.1 2.1
2018 12.8 5.9 2.7
2019 13.5 5.7 2.7

Finding and development cost per boe (3-year average)

(U.S.$)

U.S.$

Years ended March 31 Finding and development cost per boe
(3-year average)
2015 58.2
2016 16.9
2017 15.7
2018 7.7
2019 9.2

Exploration success ratio (3-year average)

(%)

%

Years ended March 31 Exploration success ratio (3-year average)
2015 52.9
2016 45.3
2017 43.8
2018 21.0
2019 60.7
  • Reserves to production ratio (Years) = Reserves as of the end of the fiscal year / Production in the fiscal year
  • Reserve replacement ratio = Proved reserves increase including acquisition / Production
  • Production cost from the year ended March 31, 2010 to the year ended March 31, 2017 has been revised to reflect changes in royalty.
  • Finding and development cost per boe = The sum of total costs incurred for exploration and development of oil and gas fields and total costs incurred for acquisitions / The sum of proved reserve extensions, acquisitions and revisions
  • Exploration success ratio = The number of net productive exploratory wells drilled / The number of net exploratory wells drilled
    Exploratory well: An exploratory well is a well drilled to find a new field, to find a new reservoir in a field previously found to be productive of oil or gas in another reservoir or to extend the limits of a known reservoir.