| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 1.14 | 1.29 | 1.02 |
| 2024 | 0.98 | 1.62 | 0.71 |
| 2023 | 0.8 | 1.16 | 0.52 |
| 2022 | 0.64 | 1.09 | 0.47 |
| 2021 | 0.47 | 0.52 | 0.41 |
| 2020 | 0.54 | 0.65 | 0.45 |
| 2019 | 0.7 | 1.16 | 0.51 |
| 2018 | 0.64 | 0.92 | 0.41 |
| 2017 | 0.75 | 1 | 0.5 |
| 2016 | 1.09 | 1.8 | 0.81 |
| 2015 | 2.37 | 3.72 | 1.58 |
| 2014 | 1.26 | 2.53 | 0.98 |
| 2013 | 1.43 | 1.91 | 1.13 |
| 2012 | 1.83 | 2.5 | 1.37 |
| 2011 | 2.06 | 2.59 | 1.5 |
| 2010 | 3.04 | 5.65 | 1.95 |
| 2009 | 4.87 | 7.82 | 1.41 |
| 2008 | 2.06 | 3.15 | 0.96 |
| 2007 | 2.56 | 4.12 | 1.03 |
| 2006 | 0.87 | 1.37 | 0.45 |
| 2005 | 0.59 | 0.73 | 0.45 |
| 2004 | 1.37 | 2.87 | 0.64 |