| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 1.02 | 1.14 | 0.91 |
| 2024 | 0.91 | 1.37 | 0.57 |
| 2023 | 1.17 | 2.5 | 0.61 |
| 2022 | 2.37 | 3.36 | 1.75 |
| 2021 | 1.64 | 3.3 | 1.12 |
| 2020 | 1.44 | 1.76 | 1.29 |
| 2019 | 1.94 | 2.43 | 1.61 |
| 2018 | 3.03 | 4.74 | 1.97 |
| 2017 | 5.07 | 6.43 | 3.58 |
| 2016 | 5.25 | 6.56 | 3.85 |
| 2015 | 7.07 | 10.25 | 4.86 |
| 2014 | 8.03 | 10.63 | 6.32 |
| 2013 | 14.48 | 19.64 | 10.03 |
| 2012 | 11.73 | 15.19 | 8.57 |
| 2011 | 11.33 | 13.91 | 8.67 |
| 2010 | 11.24 | 15.97 | 8.65 |
| 2009 | 6.57 | 8.9 | 3.92 |
| 2008 | 5.69 | 11.56 | 2.07 |
| 2007 | 6.82 | 11.87 | 2.31 |
| 2006 | 2.18 | 3.02 | 1.46 |
| 2005 | 1.31 | 1.59 | 0.86 |
| 2004 | 2.04 | 3.43 | 1.19 |