| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 22.7 | 26.92 | 17.68 |
| 2024 | 17.91 | 23.39 | 12.77 |
| 2023 | 23.51 | 28.55 | 19.76 |
| 2022 | 27.73 | 33.93 | 20.9 |
| 2021 | 0 | -0.72 | |
| 2020 | 1.3 | 1.89 | 0.76 |
| 2019 | 2 | 3.17 | 1.3 |
| 2018 | 1.72 | 2.11 | 1.08 |
| 2017 | 3.1 | 4.83 | 2.11 |
| 2016 | 30.72 | 105.91 | 4.33 |
| 2015 | 32.49 | 100.74 | 14.29 |
| 2014 | 12.72 | 17.92 | 9.06 |
| 2013 | 10.5 | 13.67 | 6.76 |
| 2012 | 7.4 | 10.76 | 5.87 |
| 2011 | 18.14 | 28.97 | 7.3 |
| 2010 | 21.03 | 31.44 | 14.02 |
| 2009 | 587.14 | 922.11 | 87.52 |
| 2008 | 0 | -7.5 | |
| 2007 | 8.33 | 40.31 | 2.97 |
| 2006 | 2.58 | 3.69 | 1.18 |
| 2005 | 1.71 | 2.51 | 1.14 |
| 2004 | 3.04 | 4.51 | 2.15 |
| 2003 | 4.01 | 4.97 | 2.87 |
| 2002 | 5.79 | 8 | 4.05 |
| 2001 | 9.7 | 11.08 | 7.45 |
| 2000 | 7.89 | 9.48 | 6.75 |
| 1999 | 7.23 | 10.65 | 5.21 |
| 1998 | 8.58 | 11.19 | 6.36 |
| 1997 | 13.45 | 21.93 | 6.64 |