| Year | Value (SE) |
|---|---|
| 2012 | 0.7018 (0.0577) |
| 2013 | 0.8202 (0.1151) |
| 2014 | 0.6586 (0.1094) |
| 2015 | 0.9451 (0.2321) |
| 2016 | 0.7444 (0.0693) |
| 2017 | 0.8919 (0.0835) |
| 2018 | 0.5804 (0.1046) |
| 2020 | 1.1290 (0.5608) |
| 2021 | 0.6722 (0.6905) |
| 2022 | 0.6380 (0.3060) |
| 2023 | 0.6989 (0.2356) |
| 2025 | 0.6860 (0.4613) |
