| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 0.91 | 1.05 | 0.83 |
| 2024 | 0.78 | 1.2 | 0.57 |
| 2023 | 0.42 | 1.06 | 0.12 |
| 2022 | 0.99 | 1.51 | 0.68 |
| 2021 | 0.7 | 0.87 | 0.52 |
| 2020 | 0.66 | 0.81 | 0.51 |
| 2019 | 0.96 | 1.18 | 0.64 |
| 2018 | 1.29 | 1.72 | 1.07 |
| 2017 | 1.98 | 2.31 | 1.63 |
| 2016 | 2.7 | 4.28 | 2.24 |
| 2015 | 4.5 | 6.58 | 3.15 |
| 2014 | 3.8 | 5.74 | 3.17 |
| 2013 | 0 | -8.78 | |
| 2012 | 0 | -7.66 | |
| 2011 | 0 | -8.38 | |
| 2010 | 0 | -8.4 | |
| 2009 | 22.58 | 25.28 | 18.49 |
| 2008 | 26.53 | 54.68 | 13.59 |
| 2007 | 50.78 | 96.11 | 26.38 |
| 2006 | 16.81 | 30.34 | 7.53 |
| 2005 | 2.19 | 7.75 | 0.25 |
| 2004 | 0.26 | 0.42 | 0.08 |
| 2003 | 0.37 | 0.57 | 0.27 |
| 2002 | 0.25 | 0.29 | 0.19 |
| 2001 | 0.18 | 0.31 | 0.07 |
| 2000 | 0.04 | 0.08 | 0.02 |
| 1999 | 0.02 | 0.02 | 0.01 |
| 1998 | 0.02 | 0.02 | 0.01 |
| 1997 | 0.02 | 0.03 | 0.02 |