| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 4.69 | 5.55 | 3.96 |
| 2024 | 3.64 | 5.5 | 2.37 |
| 2023 | 4.4 | 5.62 | 3.02 |
| 2022 | 5.95 | 7.65 | 4.67 |
| 2021 | 5.83 | 7.83 | 4.09 |
| 2020 | 4.56 | 6.95 | 2.87 |
| 2019 | 3.74 | 4.63 | 3.1 |
| 2018 | 4.13 | 4.93 | 3.3 |
| 2017 | 4.32 | 5.07 | 3.47 |
| 2016 | 5.08 | 6.19 | 4.18 |
| 2015 | 6.1 | 10.15 | 3.93 |
| 2014 | 3.95 | 5.21 | 3.12 |
| 2013 | 3.55 | 4.29 | 2.93 |
| 2012 | 4.62 | 6.27 | 3.04 |
| 2011 | 5.69 | 7.16 | 4.52 |
| 2010 | 7.01 | 9.36 | 4.95 |
| 2009 | 7.12 | 9.1 | 5.3 |
| 2008 | 8.53 | 14.86 | 3.21 |
| 2007 | 13.5 | 19.54 | 8.37 |
| 2006 | 9.65 | 13.09 | 7.73 |
| 2005 | 9.56 | 15.28 | 6.58 |