| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 2.48 | 2.81 | 2.11 |
| 2024 | 2.3 | 3.08 | 1.73 |
| 2023 | 3.4 | 4.32 | 2.63 |
| 2022 | 3.36 | 4.9 | 2.72 |
| 2021 | 2.6 | 3.76 | 2.23 |
| 2020 | 2.65 | 3.16 | 2.38 |
| 2019 | 2.89 | 3.95 | 2.1 |
| 2018 | 2.64 | 3.53 | 1.87 |
| 2017 | 4.78 | 7.24 | 3.33 |
| 2016 | 7.32 | 10.46 | 5.27 |
| 2015 | 14.84 | 28.34 | 5.71 |
| 2014 | 10.69 | 28.42 | 5.52 |
| 2013 | 5.78 | 6.82 | 5.01 |
| 2012 | 6.38 | 7.5 | 4.79 |
| 2011 | 8.27 | 12.56 | 4.76 |
| 2010 | 7.41 | 9.9 | 5.29 |
| 2009 | 4.65 | 7.12 | 2.38 |
| 2008 | 3.42 | 5.35 | 1.84 |
| 2007 | 3.82 | 6.39 | 1.57 |
| 2006 | 1.83 | 2.41 | 1.38 |
| 2005 | 1.7 | 2.22 | 1.23 |
| 2004 | 8.65 | 35.46 | 1.75 |
| 2003 | 56.59 | 88.36 | 3.18 |
| 2002 | 109.19 | 165.9 | 53.71 |
| 2001 | 69.76 | 81.17 | 59.66 |
| 2000 | 216.55 | 308.97 | 135.93 |
| 1999 | 3.98 | 5 | 2.7 |
| 1998 | 4 | 6.33 | 2.43 |
| 1997 | 3.2 | 4.94 | 2.11 |