| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 6.75 | 8.34 | 5.21 |
| 2024 | 4.36 | 8.3 | 2.22 |
| 2023 | 7.43 | 11.7 | 4.02 |
| 2022 | 5.09 | 7.37 | 3.22 |
| 2021 | 2.64 | 3.81 | 1.95 |
| 2020 | 2.83 | 3.41 | 2.3 |
| 2019 | 3.21 | 4.9 | 2.68 |
| 2018 | 3.22 | 4.49 | 2.43 |
| 2017 | 6.36 | 9.04 | 3.81 |
| 2016 | 7.85 | 9.22 | 5.34 |
| 2015 | 6.92 | 10.47 | 3.72 |
| 2014 | 3.86 | 6.52 | 2.49 |
| 2013 | 2.46 | 2.86 | 2.06 |
| 2012 | 2.6 | 3.03 | 2.19 |
| 2011 | 4.02 | 5.29 | 2.36 |
| 2010 | 4.3 | 5.39 | 3.39 |
| 2009 | 3.61 | 4.96 | 2.34 |
| 2008 | 3.19 | 5.03 | 1.81 |
| 2007 | 3.84 | 6.13 | 1.81 |
| 2006 | 1.65 | 1.95 | 1.33 |
| 2005 | 1.49 | 2 | 0.91 |
| 2004 | 1.69 | 2.52 | 1.26 |
| 2003 | 2.64 | 7.86 | 1.44 |
| 2002 | 5.11 | 5.79 | 4.63 |
| 2001 | 6.21 | 7.12 | 3.48 |
| 2000 | 4.71 | 6.27 | 2.92 |
| 1999 | 3.71 | 4.6 | 3.05 |
| 1998 | 4.54 | 5.87 | 3.13 |