| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 2.15 | 2.95 | 1.71 |
| 2024 | 1.9 | 2.61 | 1.53 |
| 2023 | 2.28 | 2.72 | 1.95 |
| 2022 | 2.48 | 3.11 | 2.07 |
| 2021 | 3.04 | 4.1 | 2.61 |
| 2020 | 4.09 | 6.18 | 2.83 |
| 2019 | 3.79 | 4.58 | 3.21 |
| 2018 | 4.22 | 6 | 2.78 |
| 2017 | 7.87 | 11.36 | 5.5 |
| 2016 | 12.13 | 16.1 | 10.91 |
| 2015 | 16.92 | 28.97 | 11.2 |
| 2014 | 8.77 | 12.59 | 6.03 |
| 2013 | 6.11 | 8.41 | 4.57 |
| 2012 | 4.53 | 5.7 | 3.48 |
| 2011 | 11.89 | 22.89 | 4.95 |
| 2010 | 12 | 28.31 | 5.35 |
| 2009 | 5.71 | 7.92 | 4.11 |
| 2008 | 6.19 | 10.06 | 3.52 |
| 2007 | 5.77 | 9.19 | 2.48 |
| 2006 | 1.52 | 2.6 | 0.69 |
| 2005 | 0.59 | 0.77 | 0.28 |
| 2004 | 0.58 | 1 | 0.34 |