| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 7.1 | 8.28 | 6.03 |
| 2024 | 6.72 | 8.21 | 5.33 |
| 2023 | 3.76 | 10.05 | 1.87 |
| 2022 | 2.12 | 2.65 | 1.7 |
| 2021 | 1.72 | 2.3 | 1.08 |
| 2020 | 1.58 | 2.11 | 1.08 |
| 2019 | 1.51 | 2.56 | 1.13 |
| 2018 | 2.42 | 3.06 | 1.4 |
| 2017 | 3.66 | 4.79 | 3 |
| 2016 | 5.69 | 9.83 | 3.09 |
| 2015 | 4.96 | 8.35 | 2.96 |
| 2014 | 4.29 | 5.68 | 3.38 |
| 2013 | 4.01 | 4.9 | 3.43 |
| 2012 | 3.69 | 4.49 | 3.04 |
| 2011 | 5.58 | 7.08 | 3.23 |
| 2010 | 6.15 | 7.52 | 4.53 |
| 2009 | 4.83 | 7.67 | 2.56 |
| 2008 | 4.02 | 6.46 | 2.03 |
| 2007 | 4.69 | 7.53 | 1.88 |
| 2006 | 9.36 | 15.01 | 1.87 |
| 2005 | 7.66 | 11.95 | 2.56 |
| 2004 | 3.7 | 5.86 | 2.69 |
| 2003 | 4.06 | 5.27 | 2.98 |
| 2002 | 4.74 | 6.37 | 1.97 |
| 2001 | 4.01 | 5.74 | 2.44 |
| 2000 | 4.32 | 6.13 | 2.73 |
| 1999 | 3.7 | 4.85 | 2.94 |
| 1998 | 5.76 | 8.85 | 3.72 |