| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 0.81 | 0.88 | 0.72 |
| 2024 | 0.9 | 1.17 | 0.7 |
| 2023 | 1 | 1.12 | 0.83 |
| 2022 | 1.03 | 1.36 | 0.82 |
| 2021 | 1.06 | 1.48 | 0.81 |
| 2020 | 1.4 | 1.85 | 1.14 |
| 2019 | 1.78 | 2.59 | 1.45 |
| 2018 | 2.51 | 4.57 | 1.46 |
| 2017 | 3.82 | 5.38 | 2.57 |
| 2016 | 4.2 | 5.59 | 3.21 |
| 2015 | 4.78 | 8.22 | 2.17 |
| 2014 | 1.92 | 3.02 | 1.39 |
| 2013 | 2.15 | 3.34 | 1.62 |
| 2012 | 3.04 | 4.44 | 2.26 |
| 2011 | 4.06 | 5.46 | 2.44 |
| 2010 | 5.62 | 10.09 | 3.72 |
| 2009 | 8.68 | 10.86 | 7.47 |
| 2008 | 0 | ||
| 2007 | 0 | ||
| 2006 | 0.91 | 1.06 | 0.81 |
| 2005 | 1.49 | 2.23 | 0.94 |
| 2004 | 2.33 | 4.52 | 1.42 |
| 2003 | 3.62 | 4.61 | 3.15 |
| 2002 | 8.86 | 10.21 | 6.89 |
| 2001 | 8.94 | 10.96 | 6.6 |
| 2000 | 10.69 | 13.37 | 6.13 |
| 1999 | 5.36 | 7.51 | 3.25 |
| 1998 | 3.74 | 4.82 | 2.77 |
| 1997 | 3.79 | 6.21 | 2.66 |