| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 2.42 | 2.6 | 2.22 |
| 2024 | 2.49 | 3.04 | 1.88 |
| 2023 | 2.79 | 3.36 | 2.4 |
| 2022 | 2.64 | 3.25 | 2.12 |
| 2021 | 2.23 | 2.76 | 1.8 |
| 2020 | 2.11 | 2.91 | 1.58 |
| 2019 | 2.25 | 3.19 | 1.9 |
| 2018 | 3.49 | 8.14 | 1.86 |
| 2017 | 7.17 | 9.02 | 5.85 |
| 2016 | 7.11 | 8.16 | 5.67 |
| 2015 | 5.93 | 9.42 | 3.17 |
| 2014 | 2.93 | 3.58 | 2.09 |
| 2013 | 2.42 | 2.9 | 2.08 |
| 2012 | 2.97 | 3.93 | 1.96 |
| 2011 | 7.09 | 10.99 | 3 |
| 2010 | 7.33 | 9.32 | 5.54 |
| 2009 | 4.19 | 6.32 | 2.1 |
| 2008 | 3.3 | 6.67 | 1.46 |
| 2007 | 6.45 | 13.2 | 4.02 |
| 2006 | 5.84 | 8.44 | 4.24 |
| 2005 | 5.48 | 6.71 | 4.37 |
| 2004 | 6.31 | 8.71 | 5.02 |
| 2003 | 9.5 | 13.11 | 4.91 |
| 2002 | 12.2 | 15.31 | 7.52 |
| 2001 | 13.66 | 16.49 | 10.32 |
| 2000 | 14.28 | 18.51 | 8.68 |
| 1999 | 8.63 | 10.85 | 6.85 |
| 1998 | 12.12 | 18.51 | 8.4 |
| 1997 | 6.29 | 9.29 | 3.95 |