| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 2.22 | 2.31 | 2.06 |
| 2024 | 2.13 | 2.66 | 1.69 |
| 2023 | 3.01 | 4.5 | 2.12 |
| 2022 | 3.96 | 5.33 | 2.74 |
| 2021 | 4.06 | 5.99 | 3.09 |
| 2020 | 2.32 | 4.28 | 1.69 |
| 2019 | 2.12 | 2.99 | 1.75 |
| 2018 | 2.43 | 3.37 | 1.67 |
| 2017 | 4.54 | 7.34 | 3.18 |
| 2016 | 4.97 | 7.45 | 0.85 |
| 2015 | 1.1 | 2.06 | 0.68 |
| 2014 | 0.61 | 0.9 | 0.46 |
| 2013 | 0.48 | 0.62 | 0.35 |
| 2012 | 0.38 | 0.42 | 0.31 |
| 2011 | 0.48 | 0.61 | 0.32 |
| 2010 | 0.57 | 0.73 | 0.44 |
| 2009 | 0.38 | 0.55 | 0.3 |
| 2008 | 0.39 | 0.65 | 0.21 |
| 2007 | 0.5 | 0.69 | 0.33 |
| 2006 | 0.3 | 0.47 | 0.19 |
| 2005 | 0.19 | 0.26 | 0.13 |
| 2004 | 0.25 | 0.62 | 0.14 |