| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 0 | ||
| 2024 | 2.1 | 2.95 | 1.44 |
| 2023 | 2.74 | 3.42 | 2.11 |
| 2022 | 2.82 | 4.21 | 2.21 |
| 2021 | 3.57 | 4.58 | 3.08 |
| 2020 | 2.83 | 5.76 | 1.88 |
| 2019 | 1.65 | 2.57 | 1.27 |
| 2018 | 3.14 | 7.95 | 1.31 |
| 2017 | 11.81 | 19 | 7.42 |
| 2016 | 12.61 | 26.45 | 7.43 |
| 2015 | 12.44 | 27.06 | 5.14 |
| 2014 | 3.85 | 6.13 | 2.97 |
| 2013 | 5.32 | 9.16 | 3.21 |
| 2012 | 8.58 | 12.05 | 5.98 |
| 2011 | 7.4 | 9.17 | 5.33 |
| 2010 | 4.95 | 6.9 | 3.57 |
| 2009 | 3.26 | 4.48 | 2.13 |
| 2008 | 3.49 | 6.65 | 1.59 |
| 2007 | 5.49 | 8.15 | 2.72 |
| 2006 | 4.32 | 6.08 | 2.58 |
| 2005 | 4.5 | 6.47 | 2.62 |
| 2004 | 4.79 | 7.69 | 2.83 |