| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 3.76 | 5.72 | 3.04 |
| 2024 | 3.11 | 4.66 | 2.14 |
| 2023 | 3.66 | 4.71 | 3.11 |
| 2022 | 3.18 | 4.22 | 2.39 |
| 2021 | 2.98 | 3.73 | 2.52 |
| 2020 | 3.45 | 5 | 2.81 |
| 2019 | 3.39 | 4.13 | 2.66 |
| 2018 | 3.26 | 4.67 | 2.59 |
| 2017 | 5.85 | 8.47 | 4.37 |
| 2016 | 6.54 | 9.23 | 5.31 |
| 2015 | 7.59 | 12.79 | 4.39 |
| 2014 | 5.63 | 8.36 | 3.84 |
| 2013 | 4.17 | 5.19 | 3.28 |
| 2012 | 4.16 | 5.65 | 2.84 |
| 2011 | 6.65 | 10.95 | 3.8 |
| 2010 | 24.75 | 57.51 | 9.42 |
| 2009 | 50.27 | 64.12 | 20.88 |
| 2008 | 16.65 | 32.77 | 5.99 |
| 2007 | 7.73 | 12.98 | 2.71 |
| 2006 | 3.26 | 3.99 | 2.56 |
| 2005 | 3.45 | 4.17 | 2.93 |
| 2004 | 2.37 | 2.37 | 2.37 |