| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 1.83 | 2.53 | 1.54 |
| 2024 | 1.36 | 1.89 | 0.97 |
| 2023 | 1.65 | 2.57 | 1.19 |
| 2022 | 2.63 | 4.1 | 1.83 |
| 2021 | 3.19 | 4.89 | 2.28 |
| 2020 | 3.05 | 3.81 | 2.59 |
| 2019 | 3.52 | 5.23 | 2.38 |
| 2018 | 3.63 | 5.84 | 2.02 |
| 2017 | 6.57 | 8.01 | 5.08 |
| 2016 | 8.03 | 9.69 | 5.23 |
| 2015 | 9.18 | 13.92 | 5.08 |
| 2014 | 4.34 | 6.01 | 2.94 |
| 2013 | 3.06 | 3.95 | 2.1 |
| 2012 | 2.45 | 3 | 1.82 |
| 2011 | 4.28 | 6.39 | 1.98 |
| 2010 | 5.98 | 8.03 | 3.87 |
| 2009 | 3.57 | 6.85 | 0.6 |
| 2008 | 0.64 | 1.11 | 0.37 |
| 2007 | 0.85 | 1.26 | 0.54 |
| 2006 | 0.67 | 0.95 | 0.45 |
| 2005 | 0.63 | 0.84 | 0.46 |
| 2004 | 1.04 | 1.89 | 0.58 |