| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 8.03 | 9.68 | 7.13 |
| 2024 | 7.4 | 11.76 | 4.39 |
| 2023 | 3.79 | 5.95 | 2.5 |
| 2022 | 2.98 | 4.2 | 1.76 |
| 2021 | 1.45 | 2.48 | 0.88 |
| 2020 | 1.28 | 1.76 | 1.02 |
| 2019 | 1.99 | 3.91 | 1.4 |
| 2018 | 3.17 | 5.55 | 1.63 |
| 2017 | 5.84 | 7.92 | 4.87 |
| 2016 | 5.24 | 7.66 | 2.8 |
| 2015 | 4.92 | 6.67 | 2.79 |
| 2014 | 2.09 | 3.13 | 1.55 |
| 2013 | 1.77 | 2.13 | 1.46 |
| 2012 | 1.86 | 2.37 | 1.42 |
| 2011 | 2.81 | 3.56 | 1.8 |
| 2010 | 3.74 | 4.66 | 2.76 |
| 2009 | 4.15 | 5.74 | 1.93 |
| 2008 | 4.12 | 7.3 | 1.51 |
| 2007 | 5.07 | 6.94 | 3.74 |
| 2006 | 3.16 | 4.41 | 1.85 |
| 2005 | 2.3 | 3.16 | 1.78 |
| 2004 | 3.43 | 4.44 | 2.76 |
| 2003 | 3.92 | 4.65 | 3.01 |
| 2002 | 5.14 | 7.03 | 3.63 |
| 2001 | 9.1 | 12.21 | 6.4 |
| 2000 | 14.74 | 23.27 | 9.48 |
| 1999 | 11.79 | 18.08 | 7.39 |
| 1998 | 12.27 | 16.53 | 7.78 |