| Year | Value (SE) |
|---|---|
| 2004 | 0.8508 (0.0636) |
| 2010 | 0.7578 (0.1260) |
| 2011 | 1.0681 (0.0917) |
| 2012 | 0.8695 (0.0574) |
| 2013 | 1.0907 (0.1586) |
| 2014 | 0.8506 (0.0770) |
| 2015 | 1.1634 (0.3921) |
| 2016 | 0.8043 (0.0365) |
| 2019 | 0.7841 (0.0892) |
| 2020 | 0.9545 (0.2213) |
| 2022 | 0.8405 (0.2139) |
| 2023 | 0.8782 (0.1372) |
