| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2024 | 1.97 | 2.76 | 1.46 |
| 2023 | 3.46 | 4.98 | 2.63 |
| 2022 | 4.81 | 7.75 | 3.75 |
| 2021 | 13.56 | 22.51 | 7.27 |
| 2020 | 17.04 | 23.61 | 13.27 |
| 2019 | 9.94 | 14.17 | 5.57 |
| 2018 | 7.27 | 9.65 | 5.37 |
| 2017 | 5.6 | 7.56 | 4.58 |
| 2016 | 7.04 | 9.85 | 4.68 |
| 2015 | 10.25 | 15.32 | 6.85 |
| 2014 | 10.45 | 15.26 | 8.15 |
| 2013 | 13.27 | 15.79 | 9.63 |
| 2012 | 8.95 | 11.54 | 6.68 |
| 2011 | 11.36 | 15.85 | 7.77 |
| 2010 | 12.95 | 18.5 | 8.61 |
| 2009 | 6.7 | 8.99 | 3.69 |
| 2008 | 3.78 | 6.81 | 2.05 |
| 2007 | 5.83 | 9.27 | 2.77 |
| 2006 | 2.08 | 2.89 | 1.12 |
| 2005 | 1.49 | 2.17 | 1.01 |
| 2004 | 1.94 | 2.47 | 1.55 |
| 2003 | 2.16 | 3.59 | 1.71 |
| 2002 | 3.92 | 4.68 | 2.72 |
| 2001 | 5.43 | 6.71 | 3.99 |
| 2000 | 4.57 | 5.75 | 3.22 |
| 1999 | 3.71 | 5.1 | 2.96 |
| 1998 | 5.41 | 6.51 | 3.95 |
| 1997 | 6.19 | 9.23 | 2.97 |