| Year | Value (SE) |
|---|---|
| 2012 | 0.7570 (0.0716) |
| 2013 | 0.7100 (0.0981) |
| 2014 | 0.7760 (0.1199) |
| 2015 | 0.8700 (0.1992) |
| 2016 | 0.5940 (0.0601) |
| 2017 | 0.7920 (0.0489) |
| 2018 | 0.7150 (0.0936) |
| 2020 | 0.6690 (0.0981) |
| 2021 | 1.0640 (0.4006) |
| 2022 | 0.6950 (0.2594) |
| 2023 | 0.7000 (0.0923) |
| 2025 | 0.8080 (0.3427) |
