Supplemental Oil And Gas Information— (Continued)
(unaudited)
arithmetic average of the first-day-of- the-month price for each month in the period October 2019 through September 2020. For oil and NGL volumes, the average West Texas Intermediate (WTI) spot price of $43.63 per Bbl is adjusted for quality, transportation fees, and market differentials. The fees associated with the transportation contract are included as a deduction to oil revenue. For gas volumes, the average Henry Hub spot price of $1.967 per MMbtu is adjusted for energy content, transportation fees, and market differentials. As a reference, the average NYMEX WTI and NYMEX Henry Hub prices for the same period were $43.40 per Bbl and $2.020 per MMbtu, respectively.
As of September 30, 2019, reserves were comprised of 67.8% crude oil, 12.5% natural gas, and 19.7% NGL. 2019 proved reserves were derived based on prices of $54.38 per Bbl of crude oil, $(0.32) per Mcf of natural gas, and $(5.19) per Bbl of NGL. Prices used in the 2019 reserve report are based on the 12-month unweighted arithmetic average of the first-day-of- the-month price for each month in the period October 2018 through September 2019. For oil and NGL volumes, the average WTI spot price of $57.69 per Bbl is adjusted for quality, transportation fees, and market differentials. The fees associated with the transportation contract are included as a deduction to oil revenue. For gas volumes, the average Henry Hub spot price of $2.870 per MMbtu is adjusted for energy content, transportation fees, and market differentials. As a reference, the average NYMEX WTI and NYMEX Henry Hub prices for the same period were $57.77 per Bbl and $2.834 per MMbtu, respectively.
As of September 30, 2018, reserves were comprised of 84.1% crude oil, 7.2% natural gas, and 8.7% NGL. 2018 proved reserves were derived based on prices of $57.92 per Bbl of crude oil, $1.62 per Mcf of natural gas and $10.25 per Bbl of NGL. Prices used in the 2018 reserve report are based on the 12-month unweighted arithmetic average of the first-day-of- the-month price for each month in the period October 2017 through September 2018. For oil and NGL volumes, the average WTI spot price of $63.43 per Bbl is adjusted for quality, transportation fees, and market differentials. The fees associated with the transportation contract are included as a deduction to oil revenue. For gas volumes, the average Henry Hub spot price of $2.914 per MMbtu is adjusted for energy content, transportation fees, and market differentials. As a reference, the average NYMEX WTI and NYMEX Henry Hub prices for the same period were $63.43 per Bbl and $2.880 per MMbtu, respectively.
For the year ended September 30, 2020, the Company had upward revisions of previous estimates of 1,162.5 Mboe. These revisions consisted of a positive revision of 1,839.6 Mboe due to pricing and differentials, a downward revision of 1,952.1 Mboe due to lease operating expenses and a positive revision of 1,275.0 Mboe which was the result of better well performance that exceeded previous estimates. The Company had extensions, discoveries and other additions to proved developed and proved non-developed reserves of 3,412.5 Mboe which consisted of 1,404.4 Mboe as a result of drilling successful wells that were previously classified as unproved locations, and the addition to proved undeveloped of 2,008.1 Mboe as a result of drilling successful wells offsetting locations that were previously unproven locations. During the fiscal year in 2020, the Company did not purchase any additional reserves.
For the year ended September 30, 2019, the Company had upward revisions of previous estimates of 9,066.2 Mboe. These revisions consisted of a positive revision of 8.0 Mboe due to pricing and differentials, a positive revision of 9.1 Mboe due to lease operating expenses and a positive revision of 9,049.1 Mboe which was the result of better well performance that exceeded previous estimates. As a result of ongoing drilling and completion activities during the fiscal year in 2019, the Company reported extensions, discoveries, and other additions of 19,579.4 Mboe. The extensions, discoveries and other additions to proved developed and proved non-developed reserves consisted of 3,833.9 Mboe as a result of drilling successful wells that were previously classified as unproved locations, and the addition to proved undeveloped of 15,745.5 Mboe as a result of drilling successful wells offsetting locations that were previously unproven locations. Additionally, during the fiscal year in 2019, the Company purchased reserves of 314.0 Mboe.
For the year ended September 30, 2018, the Company had upward revisions of previous estimates of 2,241.5 Mboe. These revisions consisted of a positive revision of 34.2 Mboe due to pricing and differentials, a positive revision of 1.6 Mboe due to lease operating expenses and a positive revision of 2,205.7 Mboe which was the result of better well performance that exceeded previous estimates. As a result of ongoing drilling and completion activities during the fiscal year in 2018, the Company reported extensions, discoveries, and other additions of 11,606.4 Mboe. The extensions, discoveries and other additions to proved developed and proved non-developed reserves consisted of 3,973.4 Mboe as a result of drilling successful wells that were previously