| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2024 | 5.52 | 8.31 | 3.77 |
| 2023 | 5.23 | 9.89 | 3.42 |
| 2022 | 2.98 | 3.94 | 2.06 |
| 2021 | 1.96 | 2.44 | 1.61 |
| 2020 | 2.3 | 2.84 | 2.01 |
| 2019 | 2.75 | 3.81 | 2.26 |
| 2018 | 2.65 | 3.68 | 1.99 |
| 2017 | 4.33 | 5.66 | 3.49 |
| 2016 | 3.95 | 5.53 | 2.99 |
| 2015 | 3.1 | 5.05 | 2.38 |
| 2014 | 2.1 | 2.99 | 1.67 |
| 2013 | 2.01 | 2.53 | 1.58 |
| 2012 | 1.9 | 2.3 | 1.57 |
| 2011 | 2.7 | 3.56 | 1.66 |
| 2010 | 2.33 | 3.68 | 1.64 |
| 2009 | 2.06 | 2.8 | 1.09 |
| 2008 | 1.95 | 2.93 | 0.87 |
| 2007 | 2.47 | 3.89 | 1.16 |
| 2006 | 1.26 | 1.96 | 1.06 |
| 2005 | 1.19 | 1.5 | 1.02 |
| 2004 | 1.92 | 2.46 | 1.49 |
| 2003 | 2.27 | 2.94 | 1.59 |
| 2002 | 3.07 | 3.45 | 2.74 |
| 2001 | 4.21 | 5.54 | 2.98 |
| 2000 | 3.55 | 4.32 | 2.61 |
| 1999 | 3.3 | 5.35 | 2.45 |
| 1998 | 4.86 | 6.26 | 3.87 |
| 1997 | 6.38 | 9.86 | 4.07 |