| Year | Value (SE) |
|---|---|
| 2011 | 0.5690 (0.0513) |
| 2012 | 0.7380 (0.0517) |
| 2013 | 0.7530 (0.0632) |
| 2014 | 0.5660 (0.0494) |
| 2015 | 0.5600 (0.0663) |
| 2016 | 0.7340 (0.0305) |
| 2017 | 0.6670 (0.0465) |
| 2018 | 0.6200 (0.0460) |
| 2019 | 0.6950 (0.0686) |
| 2020 | 0.6040 (0.0620) |
| 2021 | 0.8530 (0.1631) |
| 2022 | 0.5280 (0.0924) |
| 2024 | 0.6550 (0.1405) |
