| Year | Value (SE) |
|---|---|
| 2010 | 0.7000 (0.0349) |
| 2011 | 0.5950 (0.0270) |
| 2012 | 0.5620 (0.0324) |
| 2013 | 0.6350 (0.0559) |
| 2014 | 0.7390 (0.0691) |
| 2015 | 0.6560 (0.0585) |
| 2016 | 0.6440 (0.0338) |
| 2017 | 0.8320 (0.1086) |
| 2018 | 0.9520 (0.1656) |
| 2021 | 0.2960 (0.0702) |
| 2022 | 0.3850 (0.0885) |
| 2024 | 0.6110 (0.4089) |
