| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 2.27 | 2.82 | 1.92 |
| 2024 | 1.78 | 2.69 | 1.35 |
| 2023 | 2.29 | 2.77 | 1.94 |
| 2022 | 2.08 | 3.16 | 1.54 |
| 2021 | 1.99 | 2.27 | 1.73 |
| 2020 | 2.57 | 3.24 | 2.09 |
| 2019 | 3.07 | 4.6 | 2.19 |
| 2018 | 2.64 | 3.51 | 2.06 |
| 2017 | 3.24 | 3.88 | 2.74 |
| 2016 | 6.67 | 14.36 | 3.78 |
| 2015 | 8.58 | 16.51 | 5.12 |
| 2014 | 7.22 | 10.11 | 4.24 |
| 2013 | 4.27 | 7.15 | 2.89 |
| 2012 | 3.08 | 3.64 | 2.47 |
| 2011 | 3.38 | 4.3 | 2.54 |
| 2010 | 3.83 | 4.79 | 2.79 |
| 2009 | 3.66 | 5.65 | 1.51 |
| 2008 | 2.29 | 4.11 | 1.14 |
| 2007 | 3.12 | 4.82 | 1.82 |
| 2006 | 2.21 | 2.9 | 1.66 |
| 2005 | 2.88 | 5.2 | 1.65 |
| 2004 | 5.68 | 8.56 | 3.41 |
| 2003 | 8.16 | 9.39 | 7.42 |
| 2002 | 10.41 | 12.6 | 8.74 |
| 2001 | 15.59 | 20.46 | 11.29 |
| 2000 | 15.2 | 21.25 | 4.69 |
| 1999 | 5.47 | 7.13 | 4.69 |
| 1998 | 6.66 | 7.69 | 5.5 |
| 1997 | 6.43 | 9.79 | 4.83 |