| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 5.25 | 6.17 | 4.38 |
| 2024 | 4.07 | 7.73 | 2.95 |
| 2023 | 3.68 | 4.34 | 2.96 |
| 2022 | 3.6 | 5.27 | 2.91 |
| 2021 | 2.87 | 3.92 | 1.64 |
| 2020 | 1.94 | 2.39 | 1.5 |
| 2019 | 2.25 | 3.35 | 1.79 |
| 2018 | 2.31 | 2.68 | 1.94 |
| 2017 | 2.98 | 3.68 | 2.47 |
| 2016 | 3.73 | 4.99 | 3.21 |
| 2015 | 5.44 | 10.33 | 3.01 |
| 2014 | 2.67 | 3.42 | 2.15 |
| 2013 | 2.45 | 2.93 | 1.89 |
| 2012 | 2.61 | 3.13 | 2.21 |
| 2011 | 3.48 | 4.1 | 2.43 |
| 2010 | 4.03 | 5.22 | 3.25 |
| 2009 | 3.86 | 5.1 | 2.24 |
| 2008 | 3.66 | 6.38 | 1.72 |
| 2007 | 6.21 | 10.42 | 3.42 |
| 2006 | 2.18 | 3.32 | 1.32 |
| 2005 | 1.66 | 2.42 | 1.17 |
| 2004 | 3.12 | 4.6 | 2.27 |
| 2003 | 4.11 | 5.22 | 3.43 |
| 2002 | 4.32 | 8.07 | 2 |
| 2001 | 8.04 | 10.01 | 6.35 |
| 2000 | 8.03 | 10.04 | 5.36 |
| 1999 | 6.19 | 8.77 | 3.91 |
| 1998 | 4.99 | 6.77 | 3.47 |
| 1997 | 5.82 | 8.87 | 4.55 |