| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 1.81 | 1.93 | 1.69 |
| 2024 | 1.67 | 2.24 | 1.29 |
| 2023 | 2.39 | 3.2 | 1.88 |
| 2022 | 1.98 | 2.63 | 1.69 |
| 2021 | 1.94 | 2.44 | 1.68 |
| 2020 | 1.99 | 2.38 | 1.69 |
| 2019 | 1.96 | 2.66 | 1.55 |
| 2018 | 3.26 | 4.66 | 1.8 |
| 2017 | 4.11 | 4.93 | 3.61 |
| 2016 | 6.95 | 13.19 | 4.51 |
| 2015 | 4.81 | 14.27 | 3.56 |
| 2014 | 2.81 | 3.8 | 2.22 |
| 2013 | 2.61 | 3.06 | 2.15 |
| 2012 | 2.99 | 3.84 | 2.01 |
| 2011 | 2.69 | 3.56 | 2.14 |
| 2010 | 3.35 | 4.14 | 2.52 |
| 2009 | 2.63 | 3.54 | 2.01 |
| 2008 | 2.37 | 3.83 | 1.5 |
| 2007 | 2.94 | 4.62 | 1.45 |
| 2006 | 1.25 | 1.52 | 1.03 |
| 2005 | 1.29 | 1.71 | 0.97 |
| 2004 | 2.09 | 4.27 | 1.42 |
| 2003 | 3.54 | 4.46 | 1.61 |
| 2002 | 4.9 | 5.33 | 4.45 |
| 2001 | 5.97 | 7.03 | 4.32 |