| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 3.35 | 3.74 | 2.98 |
| 2024 | 3.07 | 4.23 | 2.3 |
| 2023 | 2.76 | 3.23 | 2.4 |
| 2022 | 2.72 | 3.8 | 2.14 |
| 2021 | 3.11 | 4.08 | 2.64 |
| 2020 | 3.3 | 4.81 | 2.87 |
| 2019 | 3.73 | 4.74 | 2.99 |
| 2018 | 3.6 | 5.16 | 2.65 |
| 2017 | 5.94 | 7.88 | 4.51 |
| 2016 | 7.72 | 9.84 | 6.94 |
| 2015 | 12.16 | 18.81 | 6.88 |
| 2014 | 5.65 | 12.05 | 3.4 |
| 2013 | 3.78 | 4.49 | 3.2 |
| 2012 | 4.62 | 5.69 | 3.43 |
| 2011 | 7.24 | 14.54 | 4.28 |
| 2010 | 8.49 | 14.72 | 5.78 |
| 2009 | 5.95 | 7.41 | 4.15 |
| 2008 | 6.17 | 14.06 | 2.3 |
| 2007 | 11.08 | 15.52 | 5.26 |
| 2006 | 4.13 | 5.5 | 3.08 |
| 2005 | 2.99 | 3.95 | 2.23 |
| 2004 | 3.67 | 4.42 | 2.96 |
| 2003 | 3.86 | 4.75 | 2.88 |
| 2002 | 5.1 | 5.72 | 3.63 |
| 2001 | 6.81 | 7.86 | 4.98 |
| 2000 | 6.41 | 8.23 | 3.52 |
| 1999 | 4.25 | 6.19 | 3.19 |
| 1998 | 4.69 | 6.13 | 3.03 |