| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 6.21 | 8.41 | 4.92 |
| 2024 | 4.99 | 7.25 | 3.83 |
| 2023 | 6.72 | 8.3 | 5.2 |
| 2022 | 11.26 | 17.31 | 6.68 |
| 2021 | 5.01 | 18.93 | 3.32 |
| 2020 | 4.51 | 6.48 | 3.43 |
| 2019 | 5.8 | 9.1 | 3.48 |
| 2018 | 4.13 | 5.81 | 2.88 |
| 2017 | 5.99 | 8.28 | 4.94 |
| 2016 | 5.89 | 8.31 | 3.93 |
| 2015 | 5.6 | 8.58 | 2.76 |
| 2014 | 3.52 | 6.4 | 2.65 |
| 2013 | 5.98 | 8.72 | 3.43 |
| 2012 | 2.97 | 3.97 | 2.15 |
| 2011 | 3.96 | 5 | 2.18 |
| 2010 | 4.32 | 5.67 | 3.3 |
| 2009 | 2.88 | 4.4 | 1.12 |
| 2008 | 2.3 | 4.72 | 0.85 |
| 2007 | 2.7 | 4.28 | 1.2 |
| 2006 | 1.22 | 1.5 | 0.9 |
| 2005 | 1.06 | 1.42 | 0.8 |
| 2004 | 1.68 | 2.23 | 1.39 |
| 2003 | 2.06 | 2.77 | 1.63 |
| 2002 | 3.05 | 3.41 | 2.34 |
| 2001 | 3.71 | 4.64 | 2.43 |
| 2000 | 2.86 | 4.69 | 1.98 |
| 1999 | 1.97 | 2.78 | 1.47 |
| 1998 | 1.74 | 2.22 | 1.47 |
| 1997 | 1.91 | 2.91 | 1.49 |