| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 4.75 | 6.1 | 3.4 |
| 2024 | 3.84 | 5.27 | 3.07 |
| 2023 | 5.08 | 8.14 | 3.76 |
| 2022 | 5.28 | 6.65 | 4.28 |
| 2021 | 2.9 | 4.91 | 1.15 |
| 2020 | 1.96 | 2.7 | 1.37 |
| 2019 | 2.7 | 4.12 | 2.06 |
| 2018 | 3.4 | 4.94 | 1.98 |
| 2017 | 5.6 | 7.31 | 4.75 |
| 2016 | 8.09 | 11.59 | 6.45 |
| 2015 | 6.43 | 9.88 | 3.13 |
| 2014 | 2.69 | 3.33 | 2.19 |
| 2013 | 7.64 | 15.75 | 2.43 |
| 2012 | 8.32 | 10.75 | 5.92 |
| 2011 | 11.13 | 14.44 | 5.88 |
| 2010 | 11.22 | 14.75 | 7.21 |
| 2009 | 5.97 | 8.59 | 3 |
| 2008 | 4.55 | 7.18 | 2.35 |
| 2007 | 4.07 | 6.22 | 2.17 |
| 2006 | 2.07 | 3 | 1.4 |
| 2005 | 1.38 | 1.89 | 0.91 |
| 2004 | 1.4 | 1.79 | 1.03 |
| 2003 | 1.87 | 2.34 | 1.32 |
| 2002 | 2.55 | 2.91 | 2.05 |