| Year | Value (SE) |
|---|---|
| 2011 | 0.5218 (0.0471) |
| 2012 | 0.6649 (0.0467) |
| 2013 | 0.6280 (0.0528) |
| 2014 | 0.4936 (0.0431) |
| 2015 | 0.4827 (0.0572) |
| 2016 | 0.6305 (0.0263) |
| 2017 | 0.6517 (0.0454) |
| 2018 | 0.5828 (0.0433) |
| 2019 | 0.5845 (0.0577) |
| 2020 | 0.5460 (0.0560) |
| 2021 | 0.7293 (0.1395) |
| 2022 | 0.4588 (0.0803) |
| 2024 | 0.5993 (0.1285) |
