| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 4.01 | 4.78 | 3.58 |
| 2024 | 3.92 | 5.59 | 3.05 |
| 2023 | 4.83 | 6.64 | 3.69 |
| 2022 | 4.46 | 5.34 | 3.62 |
| 2021 | 5.84 | 7.33 | 4.35 |
| 2020 | 7.65 | 9.96 | 5.89 |
| 2019 | 8.78 | 11.97 | 6.76 |
| 2018 | 9.44 | 13.74 | 6.94 |
| 2017 | 13.43 | 19.92 | 9.98 |
| 2016 | 19.27 | 27.04 | 12.64 |
| 2015 | 9.02 | 22.57 | 3.79 |
| 2014 | 5.31 | 6.52 | 4.02 |
| 2013 | 3.56 | 8.85 | 1.35 |
| 2012 | 1.64 | 2.16 | 1.26 |
| 2011 | 2.6 | 3.52 | 1.6 |
| 2010 | 3.74 | 6.7 | 2.47 |
| 2009 | 3.7 | 6.09 | 2.19 |
| 2008 | 2.96 | 4.45 | 1.62 |
| 2007 | 4.91 | 7.03 | 3.24 |
| 2006 | 4.03 | 4.96 | 3.25 |
| 2005 | 4.1 | 4.92 | 2.94 |
| 2004 | 5.72 | 8.06 | 4.56 |
| 2003 | 6.93 | 8.91 | 4.54 |
| 2002 | 9.25 | 11.95 | 6.77 |
| 2001 | 9.65 | 12.69 | 7.28 |
| 2000 | 8.53 | 11.33 | 5.86 |
| 1999 | 4.76 | 6.51 | 3.35 |
| 1998 | 3.69 | 5.03 | 2.84 |
| 1997 | 3.16 | 4.37 | 2.56 |