| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 1.77 | 2.69 | 1.01 |
| 2024 | 0.89 | 1.51 | 0.58 |
| 2023 | 0.9 | 0.98 | 0.83 |
| 2022 | 0.89 | 1.05 | 0.63 |
| 2021 | 0.98 | 1.2 | 0.74 |
| 2020 | 0.99 | 1.35 | 0.7 |
| 2019 | 0.88 | 1.17 | 0.75 |
| 2018 | 1.14 | 1.73 | 0.75 |
| 2017 | 2.36 | 3.21 | 1.64 |
| 2016 | 2.93 | 3.69 | 2.16 |
| 2015 | 2.81 | 4.59 | 1.57 |
| 2014 | 1.68 | 2.34 | 1.3 |
| 2013 | 1.3 | 1.77 | 0.96 |
| 2012 | 1.09 | 1.27 | 0.84 |
| 2011 | 1.6 | 2.51 | 0.98 |
| 2010 | 2.62 | 3.21 | 2.09 |
| 2009 | 1.67 | 2.49 | 0.74 |
| 2008 | 1.08 | 2.11 | 0.48 |
| 2007 | 2.63 | 3.84 | 1.6 |
| 2006 | 1.61 | 2.37 | 0.98 |
| 2005 | 1.46 | 1.9 | 1.04 |
| 2004 | 2.35 | 4.11 | 1.42 |