| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 1.93 | 2.68 | 1.49 |
| 2024 | 1.66 | 2.46 | 1.2 |
| 2023 | 2.32 | 2.84 | 1.87 |
| 2022 | 2.31 | 2.82 | 1.6 |
| 2021 | 1.71 | 3.22 | 0.77 |
| 2020 | 1.02 | 1.25 | 0.77 |
| 2019 | 1.34 | 1.94 | 1.09 |
| 2018 | 2.22 | 4.66 | 1.09 |
| 2017 | 4.72 | 7.23 | 3.62 |
| 2016 | 5.14 | 7.21 | 3.76 |
| 2015 | 6.59 | 12.5 | 3.54 |
| 2014 | 3.02 | 3.54 | 2.33 |
| 2013 | 2.27 | 2.86 | 1.81 |
| 2012 | 2.03 | 2.72 | 1.66 |
| 2011 | 2.65 | 3.62 | 1.74 |
| 2010 | 2.67 | 3.95 | 1.79 |
| 2009 | 2.26 | 3.21 | 1.24 |
| 2008 | 1.86 | 3.11 | 0.9 |
| 2007 | 2.2 | 3.33 | 1.18 |
| 2006 | 1.29 | 1.79 | 0.94 |
| 2005 | 1.24 | 1.58 | 0.94 |
| 2004 | 1.98 | 2.68 | 1.55 |
| 2003 | 2.72 | 3.73 | 1.86 |
| 2002 | 4.5 | 5.2 | 4 |
| 2001 | 6.59 | 8.04 | 4.68 |