| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 2.7 | 4.12 | 2.19 |
| 2024 | 2.15 | 2.58 | 1.65 |
| 2023 | 2.65 | 3.11 | 2.36 |
| 2022 | 2.52 | 3.05 | 2.18 |
| 2021 | 2.54 | 3.56 | 1.36 |
| 2020 | 1.59 | 2.42 | 0.91 |
| 2019 | 2.41 | 3.75 | 1.75 |
| 2018 | 3.18 | 3.41 | 1.99 |
| 2017 | 4.96 | 11.85 | 3.41 |
| 2016 | 6.71 | 7.74 | 5.05 |
| 2015 | 4.38 | 9.42 | 2.25 |
| 2014 | 2.02 | 2.75 | 1.65 |
| 2013 | 1.77 | 2.25 | 1.35 |
| 2012 | 2.18 | 2.75 | 1.47 |
| 2011 | 3.31 | 4.38 | 2.27 |
| 2010 | 3.15 | 4.19 | 2.19 |
| 2009 | 2.54 | 3.22 | 1.8 |
| 2008 | 2.66 | 4.37 | 1.4 |
| 2007 | 2.47 | 3.42 | 1.28 |
| 2006 | 1.33 | 1.65 | 1.08 |
| 2005 | 1.4 | 1.79 | 0.98 |
| 2004 | 2.22 | 2.96 | 1.77 |
| 2003 | 3.14 | 4.47 | 1.9 |
| 2002 | 8.96 | 13.84 | 3.58 |
| 2001 | 12.32 | 14.63 | 10.54 |
| 2000 | 8.79 | 13.26 | 5.65 |