| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 1.99 | 2.93 | 1.67 |
| 2024 | 1.32 | 2.12 | 0.34 |
| 2023 | 0.9 | 1.84 | 0.45 |
| 2022 | 1.44 | 1.94 | 0.79 |
| 2021 | 0.88 | 1.17 | 0.67 |
| 2020 | 1.16 | 1.69 | 0.85 |
| 2019 | 1.21 | 1.94 | 0.7 |
| 2018 | 1.09 | 1.55 | 0.63 |
| 2017 | 1.28 | 1.78 | 1.12 |
| 2016 | 1.61 | 3.05 | 1.16 |
| 2015 | 3.72 | 7.53 | 2.33 |
| 2014 | 1.78 | 3.06 | 1.29 |
| 2013 | 1.94 | 2.93 | 1.49 |
| 2012 | 1.76 | 2.87 | 1.34 |
| 2011 | 3.1 | 5.85 | 1.42 |
| 2010 | 4.11 | 6.48 | 2.74 |
| 2009 | 6.28 | 10.02 | 2.89 |
| 2008 | 4.65 | 9.91 | 1.86 |
| 2007 | 8.69 | 12.58 | 4.94 |
| 2006 | 3.95 | 5.51 | 2.53 |
| 2005 | 3.33 | 4.16 | 2.39 |
| 2004 | 6.1 | 9.93 | 3.41 |