| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 3.15 | 5.14 | 1.64 |
| 2024 | 1.83 | 2.54 | 1.31 |
| 2023 | 2.14 | 2.46 | 1.82 |
| 2022 | 2.06 | 3.09 | 1.63 |
| 2021 | 1.9 | 2.82 | 1.52 |
| 2020 | 1.83 | 2.19 | 1.66 |
| 2019 | 2.22 | 3.21 | 1.72 |
| 2018 | 2.11 | 2.91 | 1.61 |
| 2017 | 3.37 | 4.33 | 2.66 |
| 2016 | 4.14 | 4.9 | 3.63 |
| 2015 | 4.95 | 9.22 | 2.17 |
| 2014 | 5.03 | 12.6 | 2.35 |
| 2013 | 3.49 | 4.05 | 2.92 |
| 2012 | 3.81 | 5.06 | 3.16 |
| 2011 | 6.08 | 8.98 | 3.33 |
| 2010 | 5.26 | 7.84 | 3.46 |
| 2009 | 5.22 | 6.92 | 3.61 |
| 2008 | 5.16 | 9.5 | 2.36 |
| 2007 | 5.37 | 8.93 | 2.02 |
| 2006 | 2.3 | 2.75 | 1.69 |
| 2005 | 1.89 | 2.37 | 1.43 |
| 2004 | 3.23 | 4.79 | 2.24 |
| 2003 | 4.57 | 5.29 | 4.14 |
| 2002 | 5.22 | 6.49 | 4.45 |
| 2001 | 7.06 | 7.82 | 6.47 |
| 2000 | 6.71 | 9.42 | 2.58 |
| 1999 | 3.37 | 5.47 | 2.39 |
| 1998 | 4.42 | 5.76 | 3.32 |
| 1997 | 5.11 | 6.51 | 3.2 |