| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 3.98 | 4.45 | 3.46 |
| 2024 | 3.47 | 4.53 | 2.59 |
| 2023 | 4.04 | 5.31 | 3.5 |
| 2022 | 3.87 | 5.02 | 3.08 |
| 2021 | 2.99 | 3.97 | 2.45 |
| 2020 | 3.04 | 3.76 | 2.51 |
| 2019 | 3.23 | 4.32 | 2.56 |
| 2018 | 3.47 | 5.02 | 2.37 |
| 2017 | 6.31 | 9.62 | 4.43 |
| 2016 | 5.53 | 9.31 | 4.01 |
| 2015 | 5.8 | 6.59 | 3.75 |
| 2014 | 3.29 | 4.89 | 2.21 |
| 2013 | 2.5 | 2.95 | 2.05 |
| 2012 | 2.61 | 3.3 | 2.2 |
| 2011 | 4.18 | 5.39 | 2.35 |
| 2010 | 4.5 | 5.58 | 3.33 |
| 2009 | 2.86 | 4.11 | 1.56 |
| 2008 | 2.48 | 4.94 | 1.14 |
| 2007 | 4.16 | 7.63 | 1.43 |
| 2006 | 1.57 | 2.37 | 1.17 |
| 2005 | 1.38 | 2.17 | 1 |
| 2004 | 3.1 | 4.12 | 1.47 |
| 2003 | 3.78 | 4.25 | 3.36 |
| 2002 | 4.57 | 5.33 | 3.23 |
| 2001 | 4.56 | 5.03 | 3.71 |
| 2000 | 3.59 | 5.17 | 2.43 |
| 1999 | 2.85 | 3.47 | 2.51 |
| 1998 | 3.54 | 4.2 | 2.8 |