| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 0.47 | 0.54 | 0.42 |
| 2024 | 0.45 | 0.57 | 0.37 |
| 2023 | 0.51 | 0.72 | 0.4 |
| 2022 | 0.6 | 1.2 | 0.31 |
| 2021 | 0.34 | 0.4 | 0.29 |
| 2020 | 0.45 | 0.54 | 0.38 |
| 2019 | 0.45 | 0.58 | 0.38 |
| 2018 | 0.68 | 0.98 | 0.43 |
| 2017 | 0.96 | 1.06 | 0.84 |
| 2016 | 0.76 | 0.94 | 0.59 |
| 2015 | 0.99 | 1.39 | 0.71 |
| 2014 | 0.74 | 0.99 | 0.62 |
| 2013 | 0.72 | 0.96 | 0.47 |
| 2012 | 0.81 | 0.95 | 0.64 |
| 2011 | 1.06 | 1.39 | 0.77 |
| 2010 | 1.04 | 1.59 | 0.69 |
| 2009 | 1.12 | 1.72 | 0.8 |
| 2008 | 1.3 | 2.44 | 0.54 |
| 2007 | 1.29 | 2.21 | 0.69 |
| 2006 | 0.74 | 1.13 | 0.52 |
| 2005 | 0.52 | 0.86 | 0.2 |
| 2004 | 0.37 | 0.64 | 0.2 |