| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2024 | 0.8 | 0.99 | 0.61 |
| 2023 | 0.96 | 1.43 | 0.7 |
| 2022 | 1.57 | 2.32 | 1.13 |
| 2021 | 1.53 | 3.29 | 0.66 |
| 2020 | 0.61 | 0.84 | 0.5 |
| 2019 | 0.47 | 0.59 | 0.39 |
| 2018 | 0.53 | 0.7 | 0.41 |
| 2017 | 0.52 | 0.67 | 0.39 |
| 2016 | 0.51 | 0.67 | 0.41 |
| 2015 | 0.68 | 1.01 | 0.45 |
| 2014 | 0.52 | 0.74 | 0.38 |
| 2013 | 0.64 | 0.99 | 0.46 |
| 2012 | 1 | 1.35 | 0.61 |
| 2011 | 1.55 | 2.28 | 0.94 |
| 2010 | 1.89 | 2.52 | 1.35 |
| 2009 | 1.69 | 2.32 | 1 |
| 2008 | 2.5 | 4.37 | 0.66 |
| 2007 | 1.87 | 3.14 | 0.81 |
| 2006 | 0.77 | 0.92 | 0.64 |
| 2005 | 0.66 | 0.93 | 0.56 |
| 2004 | 1.08 | 2.09 | 0.65 |