| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 2.89 | 3.09 | 2.67 |
| 2024 | 2.75 | 3.51 | 2.22 |
| 2023 | 2.97 | 3.17 | 2.77 |
| 2022 | 2.85 | 3.49 | 2.21 |
| 2021 | 2.45 | 3.09 | 2.13 |
| 2020 | 2.56 | 3.04 | 2.17 |
| 2019 | 2.97 | 4.04 | 2.41 |
| 2018 | 3.33 | 4.63 | 2.48 |
| 2017 | 5.25 | 6.75 | 4.01 |
| 2016 | 4.99 | 6.19 | 4.26 |
| 2015 | 6.26 | 10.27 | 4.32 |
| 2014 | 4.21 | 5.78 | 2.46 |
| 2013 | 2.51 | 3.57 | 1.91 |
| 2012 | 3.28 | 4.61 | 2.28 |
| 2011 | 5.49 | 7.27 | 3.65 |
| 2010 | 4.38 | 5.4 | 3.57 |
| 2009 | 3.44 | 4.58 | 2.39 |
| 2008 | 3.85 | 6.75 | 1.94 |
| 2007 | 5.56 | 8.24 | 3.26 |
| 2006 | 2.92 | 3.64 | 1.71 |
| 2005 | 1.87 | 4.7 | 1.33 |
| 2004 | 6.42 | 7.06 | 4.7 |
| 2003 | 6.51 | 6.94 | 6.19 |
| 2002 | 6.11 | 6.87 | 4.46 |
| 2001 | 6.51 | 8.67 | 4.61 |
| 2000 | 5.12 | 9.66 | 2.14 |
| 1999 | 1.92 | 2.75 | 1.41 |
| 1998 | 1.9 | 2.36 | 1.5 |
| 1997 | 2.36 | 3.34 | 1.87 |