| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 1.05 | 1.14 | 0.96 |
| 2024 | 1.06 | 1.29 | 0.79 |
| 2023 | 1.25 | 1.41 | 1.03 |
| 2022 | 1.25 | 1.71 | 0.93 |
| 2021 | 1.02 | 1.29 | 0.84 |
| 2020 | 1.2 | 1.55 | 0.91 |
| 2019 | 2.23 | 4.39 | 1.32 |
| 2018 | 2.52 | 3.09 | 1.77 |
| 2017 | 4.14 | 5.2 | 3.09 |
| 2016 | 4.66 | 5.45 | 3.82 |
| 2015 | 6.19 | 9.94 | 4.22 |
| 2014 | 249.1 | 609.58 | 4.93 |
| 2013 | 492.79 | 537.35 | 449.33 |
| 2012 | 0 | -1.37 | |
| 2011 | 0 | -0.8 | |
| 2010 | 0 | -0.62 | |
| 2009 | 0 | -0.4 | |
| 2008 | 0 | -0.26 | |
| 2007 | 0 | -0.24 | |
| 2006 | 0 | -0.13 | |
| 2005 | 1.73 | 3.08 | 0.72 |
| 2004 | 3.86 | 5.68 | 2.21 |
| 2003 | 5.3 | 6.81 | 3.62 |
| 2002 | 8.87 | 9.89 | 6.59 |
| 2001 | 13.9 | 20.12 | 8.22 |
| 2000 | 14 | 26.16 | 10.36 |
| 1999 | 11.16 | 17.34 | 6.97 |
| 1998 | 9.52 | 14.31 | 5.24 |
| 1997 | 6.66 | 9.06 | 5.1 |