| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2026 | 0.68 | 0.72 | 0.61 |
| 2025 | 0.8 | 0.91 | 0.7 |
| 2024 | 0.94 | 1.27 | 0.71 |
| 2023 | 1.15 | 1.48 | 0.95 |
| 2022 | 1.15 | 1.87 | 0.64 |
| 2021 | 1.25 | 1.64 | 0.87 |
| 2020 | 0.92 | 1.83 | 0.67 |
| 2019 | 0.58 | 0.78 | 0.41 |
| 2018 | 0.55 | 0.84 | 0.33 |
| 2017 | 0.92 | 1.09 | 0.78 |
| 2016 | 1.05 | 1.2 | 0.92 |
| 2015 | 1.56 | 2.28 | 0.9 |
| 2014 | 1.43 | 1.77 | 1.12 |
| 2013 | 1.46 | 1.79 | 1.09 |
| 2012 | 0.87 | 1.14 | 0.62 |
| 2011 | 0.74 | 0.91 | 0.54 |
| 2010 | 0.98 | 1.7 | 0.68 |
| 2009 | 1.39 | 1.88 | 0.62 |
| 2008 | 1.05 | 2.21 | 0.6 |
| 2007 | 1.37 | 2.21 | 0.64 |
| 2006 | 0.42 | 0.6 | 0.33 |
| 2005 | 0.32 | 0.41 | 0.22 |
| 2004 | 0.47 | 1.04 | 0.24 |