| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 2.29 | 4.76 | 1.74 |
| 2024 | 1.69 | 2.71 | 1.13 |
| 2023 | 2.19 | 2.68 | 1.64 |
| 2022 | 2.73 | 3.65 | 2 |
| 2021 | 2.7 | 3.71 | 1.97 |
| 2020 | 1.59 | 2.6 | 0.97 |
| 2019 | 1.27 | 1.8 | 0.99 |
| 2018 | 1.26 | 1.94 | 0.93 |
| 2017 | 2.12 | 2.64 | 1.73 |
| 2016 | 3.31 | 4.19 | 2.54 |
| 2015 | 4.14 | 7 | 2.57 |
| 2014 | 2.84 | 3.87 | 2.2 |
| 2013 | 2.5 | 3.61 | 1.68 |
| 2012 | 2.5 | 3.37 | 1.43 |
| 2011 | 3.99 | 5.53 | 2.33 |
| 2010 | 6.98 | 10.86 | 4.57 |
| 2009 | 6.53 | 9.64 | 2.69 |
| 2008 | 4.9 | 8.69 | 2 |
| 2007 | 7.5 | 10.38 | 4.99 |
| 2006 | 4.79 | 7.7 | 2.17 |
| 2005 | 1.68 | 2.77 | 0.88 |
| 2004 | 2.62 | 4.6 | 1.75 |
| 2003 | 4.5 | 5.15 | 3.31 |
| 2002 | 5.04 | 6.17 | 3.93 |
| 2001 | 8.3 | 9.55 | 7.17 |
| 2000 | 9.86 | 11.81 | 7.35 |
| 1999 | 7.81 | 11.08 | 5.44 |