| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 1.25 | 1.34 | 1.16 |
| 2024 | 1.26 | 1.41 | 1.13 |
| 2023 | 1.46 | 1.82 | 1.22 |
| 2022 | 1.93 | 2.57 | 1.45 |
| 2021 | 3.23 | 5.72 | 1.83 |
| 2020 | 8.53 | 16.86 | 4.63 |
| 2019 | 6.19 | 8.16 | 5.03 |
| 2018 | 6.12 | 7.71 | 5 |
| 2017 | 8 | 10.8 | 6.39 |
| 2016 | 6.49 | 9.32 | 4.07 |
| 2015 | 4.22 | 6.11 | 2.77 |
| 2014 | 2.18 | 3.26 | 1.76 |
| 2013 | 2.97 | 4.22 | 2.21 |
| 2012 | 4.02 | 5.21 | 3.26 |
| 2011 | 5.74 | 9.22 | 3.71 |
| 2010 | 3.54 | 5.11 | 2.36 |
| 2009 | 2.6 | 3.49 | 1.76 |
| 2008 | 2.98 | 5.75 | 1.4 |
| 2007 | 4.3 | 6.32 | 2.04 |
| 2006 | 2.34 | 2.94 | 1.65 |
| 2005 | 1.55 | 2.18 | 1.29 |
| 2004 | 1.95 | 2.73 | 1.39 |