| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 1.71 | 2.84 | 1.26 |
| 2024 | 1.4 | 1.73 | 1.06 |
| 2023 | 1.53 | 1.95 | 1.33 |
| 2022 | 1.43 | 1.68 | 1.2 |
| 2021 | 1.66 | 2.1 | 1.42 |
| 2020 | 1.52 | 2.32 | 1.2 |
| 2019 | 1.58 | 2.12 | 1.19 |
| 2018 | 1.76 | 2.61 | 1.17 |
| 2017 | 3.7 | 6.95 | 2.13 |
| 2016 | 5.5 | 7.51 | 2.48 |
| 2015 | 3.53 | 5.98 | 1.98 |
| 2014 | 2.34 | 3.59 | 1.61 |
| 2013 | 2.08 | 2.85 | 1.48 |
| 2012 | 2.95 | 3.67 | 2.32 |
| 2011 | 4.97 | 9.55 | 2.34 |
| 2010 | 4.78 | 9.11 | 2.79 |
| 2009 | 3.93 | 5.7 | 1.86 |
| 2008 | 3.83 | 9.15 | 1.33 |
| 2007 | 5.74 | 12.35 | 2.13 |
| 2006 | 1.82 | 2.67 | 1.27 |
| 2005 | 1.75 | 2.5 | 1.18 |
| 2004 | 2.97 | 4.28 | 2.25 |
| 2003 | 3.21 | 4.11 | 1.77 |