| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 8.44 | 9.89 | 6.7 |
| 2024 | 8.91 | 15.91 | 5.85 |
| 2023 | 4.58 | 12.01 | 2.46 |
| 2022 | 2.92 | 4.38 | 2.13 |
| 2021 | 2.33 | 3.07 | 1.76 |
| 2020 | 2.74 | 3.46 | 2.35 |
| 2019 | 3.67 | 4.72 | 3.06 |
| 2018 | 3.64 | 4.7 | 2.59 |
| 2017 | 4.61 | 6.46 | 3.39 |
| 2016 | 6.06 | 8.56 | 4.92 |
| 2015 | 15.44 | 47.68 | 4.18 |
| 2014 | 8.62 | 14.79 | 6.46 |
| 2013 | 7.72 | 10.13 | 6.29 |
| 2012 | 9.41 | 12.51 | 6.75 |
| 2011 | 18 | 27.09 | 8.92 |
| 2010 | 25.12 | 30.13 | 18.86 |
| 2009 | 17.8 | 28.75 | 8.22 |
| 2008 | 11.38 | 35.33 | 4.39 |
| 2007 | 5.96 | 10.87 | 1.45 |
| 2006 | 2.13 | 3.35 | 1.44 |
| 2005 | 1.72 | 2.31 | 1.22 |
| 2004 | 2.52 | 3.54 | 1.89 |
| 2003 | 2.65 | 3.4 | 1.97 |
| 2002 | 3.76 | 4.37 | 2.66 |
| 2001 | 4.91 | 6.06 | 3.39 |
| 2000 | 4.87 | 5.85 | 3.95 |
| 1999 | 3.44 | 5.19 | 2.67 |
| 1998 | 3.46 | 4.77 | 2.62 |
| 1997 | 3.81 | 5.89 | 2.55 |