| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 1.05 | 1.18 | 0.98 |
| 2024 | 1.02 | 1.46 | 0.82 |
| 2023 | 1.1 | 1.6 | 0.85 |
| 2022 | 0.83 | 1.12 | 0.72 |
| 2021 | 0.8 | 0.89 | 0.73 |
| 2020 | 0.91 | 1.02 | 0.82 |
| 2019 | 1 | 1.27 | 0.86 |
| 2018 | 1.09 | 1.42 | 0.87 |
| 2017 | 1.67 | 2.1 | 1.32 |
| 2016 | 1.86 | 2.47 | 1.68 |
| 2015 | 2.75 | 4.79 | 2.31 |
| 2014 | 3.13 | 6.36 | 2.23 |
| 2013 | 2.68 | 3.66 | 2.19 |
| 2012 | 3.26 | 4.48 | 2.13 |
| 2011 | 4.53 | 4.96 | 3.95 |
| 2010 | 0 | ||
| 2009 | 0 | ||
| 2008 | 0 | -6.46 | |
| 2007 | 7.09 | 11.05 | 3.91 |
| 2006 | 2.64 | 4.59 | 1.23 |
| 2005 | 1.37 | 1.93 | 0.9 |
| 2004 | 2.35 | 3.21 | 1.68 |
| 2003 | 3.28 | 4.85 | 2.29 |
| 2002 | 4.68 | 5.51 | 3.92 |
| 2001 | 6 | 7.61 | 4.48 |
| 2000 | 9.01 | 13.4 | 5.28 |
| 1999 | 4.78 | 6.16 | 3.85 |
| 1998 | 5.71 | 6.8 | 4.42 |