| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 3.11 | 4.06 | 2.44 |
| 2024 | 1.62 | 4.61 | 0.89 |
| 2023 | 1.36 | 1.57 | 1.19 |
| 2022 | 1.45 | 2.03 | 1.13 |
| 2021 | 1.86 | 2.25 | 1.61 |
| 2020 | 2.19 | 3.63 | 1.27 |
| 2019 | 1.27 | 1.81 | 0.97 |
| 2018 | 2.28 | 5.77 | 0.96 |
| 2017 | 4.33 | 5.76 | 3.53 |
| 2016 | 4.09 | 4.82 | 2.98 |
| 2015 | 5.48 | 9.56 | 1.81 |
| 2014 | 1.42 | 1.91 | 1.08 |
| 2013 | 1.03 | 1.24 | 0.84 |
| 2012 | 1.02 | 1.24 | 0.83 |
| 2011 | 1.34 | 1.66 | 0.98 |
| 2010 | 1.88 | 2.54 | 1.42 |
| 2009 | 1.66 | 2.6 | 1.04 |
| 2008 | 1.37 | 2.06 | 0.88 |
| 2007 | 1.41 | 2.01 | 0.77 |
| 2006 | 0.74 | 0.84 | 0.58 |
| 2005 | 0.56 | 0.73 | 0.39 |
| 2004 | 0.92 | 1.26 | 0.68 |
| 2003 | 1.14 | 1.35 | 0.89 |
| 2002 | 1.25 | 1.57 | 0.7 |
| 2001 | 1.53 | 2.42 | 0.92 |
| 2000 | 2.74 | 3.59 | 2.3 |
| 1999 | 3.4 | 4.84 | 2.52 |
| 1998 | 4.01 | 5.62 | 2.92 |
| 1997 | 5.06 | 7.44 | 3.33 |