| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 0.86 | 0.95 | 0.81 |
| 2024 | 0.85 | 1.11 | 0.68 |
| 2023 | 1.08 | 1.45 | 0.88 |
| 2022 | 0.95 | 1.2 | 0.68 |
| 2021 | 0.97 | 1.24 | 0.85 |
| 2020 | 1.05 | 1.42 | 0.7 |
| 2019 | 0.74 | 0.86 | 0.61 |
| 2018 | 1.04 | 1.63 | 0.62 |
| 2017 | 1.85 | 2.93 | 1.17 |
| 2016 | 1.31 | 1.76 | 1.03 |
| 2015 | 1.36 | 2.04 | 0.92 |
| 2014 | 1 | 1.31 | 0.81 |
| 2013 | 0.91 | 1.15 | 0.72 |
| 2012 | 0.83 | 1.02 | 0.62 |
| 2011 | 1.58 | 2.41 | 0.88 |
| 2010 | 1.78 | 2.31 | 1.26 |
| 2009 | 1.51 | 2.17 | 0.72 |
| 2008 | 0.99 | 1.93 | 0.39 |
| 2007 | 1.75 | 2.42 | 1.12 |
| 2006 | 1.1 | 1.35 | 0.88 |
| 2005 | 0.92 | 1.2 | 0.55 |
| 2004 | 1.78 | 4.02 | 0.94 |