| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 4.3 | 4.81 | 3.76 |
| 2024 | 4.28 | 5.16 | 3.51 |
| 2023 | 4.17 | 4.6 | 3.6 |
| 2022 | 4.32 | 5.41 | 3.62 |
| 2021 | 5.22 | 7.51 | 3.51 |
| 2020 | 8.64 | 13.69 | 6.3 |
| 2019 | 5.96 | 7.31 | 5.05 |
| 2018 | 5.85 | 7.29 | 4.83 |
| 2017 | 5.61 | 7.13 | 4.31 |
| 2016 | 4.55 | 5.84 | 3.49 |
| 2015 | 4.63 | 5.78 | 3.52 |
| 2014 | 5.95 | 8.13 | 4.27 |
| 2013 | 7.32 | 9.12 | 5.88 |
| 2012 | 11.32 | 18.46 | 5.48 |
| 2011 | 13.23 | 17.25 | 9.24 |
| 2010 | 11.22 | 18.54 | 9.49 |
| 2009 | 9.47 | 12.11 | 7.7 |
| 2008 | 10.79 | 18.64 | 6.87 |
| 2007 | 11.55 | 17.96 | 6.12 |
| 2006 | 7.61 | 9.64 | 4.02 |
| 2005 | 4.39 | 5.41 | 3.65 |
| 2004 | 3.92 | 6.12 | 2.93 |
| 2003 | 4.19 | 5.21 | 2.91 |
| 2002 | 7.45 | 8.96 | 6.46 |
| 2001 | 9.49 | 11.07 | 6.87 |
| 2000 | 9.01 | 10.57 | 6.97 |
| 1999 | 8.42 | 12.11 | 5.39 |