| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 1.59 | 2.04 | 1.36 |
| 2024 | 1.15 | 1.89 | 0.92 |
| 2023 | 1.19 | 1.26 | 1.07 |
| 2022 | 1.33 | 1.89 | 1.06 |
| 2021 | 1.32 | 1.69 | 1.12 |
| 2020 | 1.2 | 1.69 | 0.87 |
| 2019 | 1.08 | 1.39 | 0.91 |
| 2018 | 1.24 | 1.71 | 0.93 |
| 2017 | 2.14 | 3.16 | 1.55 |
| 2016 | 2.51 | 3.26 | 1.7 |
| 2015 | 2.69 | 5.51 | 1.74 |
| 2014 | 1.61 | 2.19 | 1.26 |
| 2013 | 1.59 | 2.23 | 1.21 |
| 2012 | 2.13 | 3.04 | 1.15 |
| 2011 | 1.95 | 2.46 | 1.2 |
| 2010 | 3.53 | 5.5 | 2.32 |
| 2009 | 3.57 | 6.01 | 1.34 |
| 2008 | 1.45 | 2.25 | 0.87 |
| 2007 | 1.75 | 2.49 | 0.98 |
| 2006 | 0.79 | 1.07 | 0.54 |
| 2005 | 0.72 | 1.02 | 0.36 |
| 2004 | 1.09 | 1.97 | 0.68 |