| 2019 | 2020 | 2021 | 2022 | 2023 | Change 23/22 | % Change 23/22 | Avg. Gr. (%) | Mean | SD | Min | Max | CV | Share in 2023 (%) | |
| Algeria | 1.09 | 0.94 | 0.94 | 0.99 | 1.00 | 0.01 | 1.26 | -2.18 | 0.99 | 0.06 | 0.94 | 1.09 | 0.06 | 4.07 |
| Congo | 0.32 | 0.29 | 0.26 | 0.25 | 0.25 | 0.01 | 2.69 | -5.25 | 0.27 | 0.03 | 0.25 | 0.32 | 0.11 | 1.04 |
| Equatorial Guinea | 0.11 | 0.11 | 0.09 | 0.08 | 0.05 | -0.03 | -33.00 | -16.30 | 0.09 | 0.02 | 0.05 | 0.11 | 0.27 | 0.22 |
| Gabon | 0.21 | 0.20 | 0.19 | 0.19 | 0.21 | 0.02 | 10.02 | 0.01 | 0.20 | 0.01 | 0.19 | 0.21 | 0.05 | 0.87 |
| IR Iran | 0.94 | 0.69 | 1.10 | 1.28 | 1.73 | 0.45 | 34.82 | 16.62 | 1.15 | 0.39 | 0.69 | 1.73 | 0.34 | 7.06 |
| Iraq | 4.07 | 3.58 | 3.60 | 3.88 | 3.66 | -0.22 | -5.67 | -2.62 | 3.76 | 0.21 | 3.58 | 4.07 | 0.06 | 14.95 |
| Kuwait | 2.62 | 2.35 | 2.34 | 2.59 | 2.53 | -0.06 | -2.23 | -0.88 | 2.49 | 0.13 | 2.34 | 2.62 | 0.05 | 10.33 |
| Libya | 1.06 | 0.41 | 1.18 | 1.02 | 1.11 | 0.10 | 9.34 | 1.34 | 0.96 | 0.31 | 0.41 | 1.18 | 0.32 | 4.55 |
| Nigeria | 2.03 | 1.88 | 1.60 | 1.39 | 1.48 | 0.09 | 6.53 | -7.59 | 1.68 | 0.27 | 1.39 | 2.03 | 0.16 | 6.03 |
| Saudi Arabia | 8.34 | 7.68 | 7.57 | 8.83 | 7.93 | -0.90 | -10.19 | -1.24 | 8.07 | 0.52 | 7.57 | 8.83 | 0.06 | 32.35 |
| United Arab Emirates | 3.30 | 3.26 | 3.20 | 3.62 | 3.79 | 0.17 | 4.80 | 3.58 | 3.43 | 0.26 | 3.20 | 3.79 | 0.08 | 15.47 |
| Venezuela | 0.94 | 0.56 | 0.52 | 0.61 | 0.75 | 0.14 | 22.27 | -5.55 | 0.68 | 0.17 | 0.52 | 0.94 | 0.26 | 3.06 |
| Total OPEC | 25.03 | 21.95 | 22.58 | 24.74 | 24.52 | -0.22 | -0.90 | -0.51 | 23.76 | 1.40 | 21.95 | 25.03 | 0.06 | 100.00 |