| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 1.12 | 1.67 | 0.91 |
| 2024 | 0.94 | 1.08 | 0.68 |
| 2023 | 1.06 | 1.17 | 0.93 |
| 2022 | 1.16 | 1.69 | 0.89 |
| 2021 | 1.24 | 1.51 | 1.05 |
| 2020 | 1.44 | 1.82 | 1.13 |
| 2019 | 1.18 | 1.51 | 0.88 |
| 2018 | 1.29 | 1.8 | 0.82 |
| 2017 | 1.91 | 2.28 | 1.6 |
| 2016 | 2.46 | 2.91 | 1.85 |
| 2015 | 2.75 | 3.64 | 1.61 |
| 2014 | 1.42 | 1.95 | 1.14 |
| 2013 | 1.04 | 1.25 | 0.92 |
| 2012 | 1.07 | 1.22 | 0.92 |
| 2011 | 1.49 | 1.97 | 0.98 |
| 2010 | 1.8 | 2.39 | 1.32 |
| 2009 | 1.8 | 2.5 | 0.87 |
| 2008 | 1.38 | 2.26 | 0.73 |
| 2007 | 1.97 | 2.77 | 1.03 |
| 2006 | 0.96 | 1.15 | 0.79 |
| 2005 | 0.85 | 1.07 | 0.71 |
| 2004 | 1.48 | 2.11 | 1.05 |
| 2003 | 1.97 | 2.32 | 1.76 |
| 2002 | 2.04 | 2.25 | 1.76 |
| 2001 | 2.67 | 3.42 | 1.8 |
| 2000 | 2.93 | 4.08 | 2.42 |
| 1999 | 2.93 | 4.25 | 2.37 |
| 1998 | 4.85 | 7.78 | 2.61 |
| 1997 | 5.89 | 8.59 | 3.39 |