| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 3.38 | 3.71 | 3.01 |
| 2024 | 3.35 | 5.11 | 2.45 |
| 2023 | 3.39 | 5.2 | 2.17 |
| 2022 | 2.53 | 3.25 | 1.92 |
| 2021 | 2.14 | 3.9 | 0.87 |
| 2020 | 0.84 | 1.3 | 0.58 |
| 2019 | 0.66 | 0.85 | 0.54 |
| 2018 | 0.82 | 1.15 | 0.53 |
| 2017 | 1.16 | 1.46 | 0.96 |
| 2016 | 1.14 | 1.33 | 0.96 |
| 2015 | 1.54 | 2.46 | 1.09 |
| 2014 | 0.99 | 1.29 | 0.78 |
| 2013 | 0.9 | 1.15 | 0.72 |
| 2012 | 0.79 | 0.98 | 0.62 |
| 2011 | 1.34 | 1.81 | 0.77 |
| 2010 | 2.26 | 4.3 | 1.56 |
| 2009 | 1.98 | 2.67 | 1.16 |
| 2008 | 2.77 | 7.3 | 0.86 |
| 2007 | 8.26 | 20.58 | 4.16 |
| 2006 | 3.1 | 7.03 | 2.45 |
| 2005 | 5.1 | 9.9 | 2.57 |
| 2004 | 62.21 | 514.86 | 9.24 |
| 2003 | 517.91 | 743.79 | 260 |
| 2002 | 22.25 | 33.52 | 4.04 |
| 2001 | 9.38 | 11.86 | 6.61 |
| 2000 | 9.46 | 12.86 | 5.17 |
| 1999 | 4.88 | 6.59 | 3.38 |
| 1998 | 3.57 | 4.66 | 2.83 |
| 1997 | 3.91 | 6.2 | 2.57 |