| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 0 | ||
| 2024 | 0 | ||
| 2023 | 0.57 | 0.65 | 0.49 |
| 2022 | 0.49 | 0.64 | 0.41 |
| 2021 | 0.6 | 0.79 | 0.43 |
| 2020 | 0.78 | 0.89 | 0.61 |
| 2019 | 0.83 | 1.14 | 0.68 |
| 2018 | 1.26 | 1.4 | 0.72 |
| 2017 | 1.46 | 1.68 | 1.27 |
| 2016 | 1.39 | 2.01 | 1.14 |
| 2015 | 1.48 | 2.41 | 0.77 |
| 2014 | 0.83 | 1.44 | 0.56 |
| 2013 | 0.74 | 1 | 0.56 |
| 2012 | 0.67 | 0.88 | 0.47 |
| 2011 | 0.93 | 1.55 | 0.49 |
| 2010 | 1.39 | 2.51 | 0.83 |
| 2009 | 1.07 | 2.51 | 0.41 |
| 2008 | 0.66 | 1.27 | 0.31 |
| 2007 | 1.16 | 1.63 | 0.52 |
| 2006 | 0.56 | 0.74 | 0.44 |
| 2005 | 0.37 | 0.52 | 0.21 |
| 2004 | 0.4 | 0.7 | 0.26 |