| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 2.73 | 3.12 | 2.38 |
| 2024 | 2.72 | 3.34 | 2.16 |
| 2023 | 4.05 | 5.71 | 2.89 |
| 2022 | 5.34 | 8.6 | 3.65 |
| 2021 | 7.71 | 10.33 | 5.98 |
| 2020 | 6.17 | 8.39 | 4.09 |
| 2019 | 3.58 | 4.56 | 2.6 |
| 2018 | 2.67 | 3.32 | 2.14 |
| 2017 | 3.23 | 4.06 | 2.67 |
| 2016 | 3.3 | 3.86 | 2.77 |
| 2015 | 4.21 | 7.02 | 2.87 |
| 2014 | 3.73 | 5.2 | 2.54 |
| 2013 | 3.93 | 6.82 | 2.6 |
| 2012 | 2.73 | 3.05 | 2.33 |
| 2011 | 2.97 | 3.68 | 2.39 |
| 2010 | 2.88 | 3.59 | 2.12 |
| 2009 | 2.79 | 3.96 | 1.51 |
| 2008 | 2.29 | 4.56 | 1.1 |
| 2007 | 5.12 | 9.81 | 2.87 |
| 2006 | 1.81 | 4.01 | 1.34 |
| 2005 | 1.78 | 2.35 | 1.19 |
| 2004 | 3.42 | 5.38 | 2.19 |
| 2003 | 4.21 | 5.76 | 2.64 |
| 2002 | 6.13 | 7.85 | 4.74 |
| 2001 | 6.34 | 7.23 | 5.46 |
| 2000 | 5.77 | 7.75 | 4.21 |
| 1999 | 6.17 | 10.46 | 4.39 |
| 1998 | 3.45 | 5.05 | 2.15 |