| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 1.22 | 1.48 | 0.96 |
| 2024 | 1.08 | 1.42 | 0.84 |
| 2023 | 1.16 | 1.5 | 0.84 |
| 2022 | 1 | 1.35 | 0.79 |
| 2021 | 1.37 | 1.87 | 1.14 |
| 2020 | 1.16 | 1.64 | 0.89 |
| 2019 | 1.19 | 1.72 | 0.96 |
| 2018 | 1.58 | 2.49 | 1.01 |
| 2017 | 6.25 | 14.65 | 2.11 |
| 2016 | 3.01 | 4.19 | 1.83 |
| 2015 | 1.76 | 3.16 | 1.15 |
| 2014 | 1.02 | 1.47 | 0.84 |
| 2013 | 0.93 | 1.05 | 0.74 |
| 2012 | 1.31 | 1.72 | 0.87 |
| 2011 | 2.01 | 2.41 | 1.41 |
| 2010 | 1.62 | 2.16 | 1.07 |
| 2009 | 0.96 | 1.27 | 0.69 |
| 2008 | 1.14 | 2.14 | 0.51 |
| 2007 | 1.66 | 2.55 | 0.58 |
| 2006 | 0.52 | 0.66 | 0.4 |
| 2005 | 0.56 | 0.71 | 0.4 |
| 2004 | 0.93 | 1.46 | 0.67 |