| Year | Value (SE) |
|---|---|
| 2012 | 0.6260 (0.0514) |
| 2013 | 0.7537 (0.1052) |
| 2014 | 0.6698 (0.1111) |
| 2015 | 0.8288 (0.2034) |
| 2016 | 0.7087 (0.0660) |
| 2017 | 0.7938 (0.0743) |
| 2018 | 0.5688 (0.1023) |
| 2020 | 0.9755 (0.4845) |
| 2021 | 0.5593 (0.5745) |
| 2022 | 0.5793 (0.2778) |
| 2023 | 0.5430 (0.1831) |
| 2025 | 0.5975 (0.4018) |
