| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 0.91 | 0.95 | 0.86 |
| 2024 | 0.98 | 1.11 | 0.8 |
| 2023 | 1.03 | 1.16 | 0.9 |
| 2022 | 1.2 | 1.68 | 0.87 |
| 2021 | 1.87 | 2.87 | 1.45 |
| 2020 | 1.66 | 2.11 | 1.34 |
| 2019 | 2.02 | 3.46 | 1.5 |
| 2018 | 2.86 | 3.47 | 1.81 |
| 2017 | 2.19 | 2.86 | 1.72 |
| 2016 | 2.37 | 3.38 | 1.86 |
| 2015 | 2.5 | 4.29 | 1.54 |
| 2014 | 1.55 | 1.91 | 1.33 |
| 2013 | 1.97 | 2.69 | 1.57 |
| 2012 | 3.43 | 5.02 | 2.02 |
| 2011 | 46.09 | 149.04 | 3.09 |
| 2010 | 16.81 | 34.93 | 7.05 |
| 2009 | 4.9 | 8.31 | 1.84 |
| 2008 | 4.05 | 9.05 | 1.41 |
| 2007 | 6.29 | 11.6 | 2.35 |
| 2006 | 2.21 | 2.96 | 1.55 |
| 2005 | 1.74 | 2.46 | 1.19 |
| 2004 | 3.11 | 4.71 | 2.34 |
| 2003 | 3.57 | 4.44 | 2.2 |
| 2002 | 5.08 | 5.57 | 3.83 |
| 2001 | 6.99 | 8.45 | 5.35 |
| 2000 | 6.86 | 9.1 | 4.51 |
| 1999 | 4.97 | 5.95 | 4.19 |
| 1998 | 7.06 | 9.45 | 5.26 |