| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 3.19 | 3.49 | 2.94 |
| 2024 | 3.11 | 3.56 | 2.4 |
| 2023 | 3.6 | 4.5 | 3.08 |
| 2022 | 5.23 | 7.65 | 3.36 |
| 2021 | 7.72 | 11.07 | 5.73 |
| 2020 | 7.91 | 10.5 | 6.3 |
| 2019 | 6.8 | 7.99 | 5.13 |
| 2018 | 6.53 | 8.91 | 5.08 |
| 2017 | 5.84 | 8.37 | 4.27 |
| 2016 | 4.71 | 5.64 | 4.03 |
| 2015 | 5.28 | 6.79 | 4.22 |
| 2014 | 4.53 | 5.27 | 3.73 |
| 2013 | 6.02 | 8.88 | 4.02 |
| 2012 | 5.39 | 6.58 | 4.42 |
| 2011 | 6.6 | 7.84 | 5.44 |
| 2010 | 7.51 | 9.22 | 6.18 |
| 2009 | 4.13 | 6.88 | 1.52 |
| 2008 | 3.19 | 7.69 | 1.19 |
| 2007 | 5.96 | 6.97 | 4.63 |
| 2006 | 3.99 | 5.58 | 2.29 |
| 2005 | 2.36 | 2.68 | 1.73 |
| 2004 | 2.39 | 3.38 | 1.72 |
| 2003 | 2.74 | 3.17 | 1.51 |
| 2002 | 3.81 | 4.56 | 3.19 |
| 2001 | 4.56 | 5.58 | 3.48 |
| 2000 | 4.45 | 5.17 | 3.84 |
| 1999 | 5.14 | 8.36 | 3.75 |
| 1998 | 6.66 | 8.14 | 5.32 |
| 1997 | 11.44 | 14.76 | 8.45 |