| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 2.49 | 76 |
| 2015 | 2.4 | 81 |
| 2014 | 2.29 | 85 |
| 2013 | 2.21 | 89 |
| 2012 | 1.84 | 100 |
| 2011 | 1.33 | 121 |
| 2010 | 1.25 | 128 |
| 2009 | 1.2 | 134 |
| 2008 | 0.94 | 146 |
| 2007 | 0.95 | 145 |
| 2006 | 1.07 | 143 |
| 2005 | 1.12 | 138 |
| 2004 | 1.21 | 135 |
| 2003 | 1.04 | 139 |
| 2002 | 0.92 | 151 |
| 2001 | 0.94 | 148 |
| 2000 | 1.19 | 139 |
| 1999 | 0.91 | 145 |
| 1998 | 0.75 | 154 |
| 1997 | 0.68 | 162 |
| 1996 | 0.7 | 160 |
| 1995 | 0.22 | 180 |
| 1994 | -.81 | 202 |
| 1993 | -.74 | 202 |
| 1992 | 0.39 | 177 |
| 1991 | 0.87 | 162 |
| 1990 | 1.17 | 152 |
| 1989 | 1.67 | 144 |
| 1988 | 1.63 | 149 |
| 1987 | 1.77 | 144 |
| 1986 | 1.76 | 140 |