| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 3 | 3.32 | 2.72 |
| 2024 | 2.45 | 3.25 | 2.04 |
| 2023 | 2.09 | 2.34 | 1.75 |
| 2022 | 1.83 | 2.07 | 1.57 |
| 2021 | 2.48 | 3.71 | 1.83 |
| 2020 | 3.66 | 4.35 | 3.02 |
| 2019 | 3.79 | 4.49 | 3.38 |
| 2018 | 3.57 | 4.29 | 3.07 |
| 2017 | 4.38 | 4.73 | 3.95 |
| 2016 | 4.99 | 6.17 | 4.4 |
| 2015 | 5.43 | 7.25 | 3.82 |
| 2014 | 2.84 | 5.15 | 2.2 |
| 2013 | 2.3 | 2.71 | 1.89 |
| 2012 | 2.62 | 3.35 | 2.09 |
| 2011 | 4.25 | 5.58 | 3.05 |
| 2010 | 7.43 | 11.98 | 4.8 |
| 2009 | 11.06 | 12.99 | 9.05 |
| 2008 | 14.37 | 26.55 | 8.69 |
| 2007 | 18.35 | 27.52 | 10.01 |
| 2006 | 9.14 | 11.24 | 7.56 |
| 2005 | 8.57 | 11.01 | 5.24 |
| 2004 | 10.55 | 19.74 | 5.61 |