| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 0 | ||
| 2024 | 0 | ||
| 2023 | 0 | ||
| 2022 | 0 | -0.05 | |
| 2021 | 19.37 | 70.06 | 3.89 |
| 2020 | 3.63 | 7.83 | 0.39 |
| 2019 | 1.03 | 1.44 | 0.68 |
| 2018 | 2.24 | 3.92 | 1.02 |
| 2017 | 5.18 | 7.13 | 2.87 |
| 2016 | 6.45 | 8.18 | 5.19 |
| 2015 | 22.5 | 120.51 | 6.96 |
| 2014 | 16.7 | 23.32 | 11.65 |
| 2013 | 10.43 | 13.22 | 8.3 |
| 2012 | 9.33 | 11.98 | 7.72 |
| 2011 | 14.07 | 18.19 | 9 |
| 2010 | 12.62 | 16.53 | 8.69 |
| 2009 | 8.99 | 13.1 | 3.79 |
| 2008 | 9.03 | 20.09 | 2.73 |
| 2007 | 7.1 | 13.91 | 1.98 |
| 2006 | 1.91 | 2.55 | 1.38 |
| 2005 | 1.59 | 2.01 | 1.27 |
| 2004 | 2.44 | 3.4 | 1.73 |
| 2003 | 2.83 | 3.46 | 2.36 |
| 2002 | 4.22 | 5.06 | 2.89 |
| 2001 | 5.59 | 7.05 | 3.88 |
| 2000 | 6.34 | 8.08 | 4.26 |
| 1999 | 3.69 | 4.68 | 2.45 |
| 1998 | 2.69 | 3.16 | 2.12 |
| 1997 | 2.27 | 3.35 | 1.78 |