| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 11.66 | 146 |
| 2015 | 11.12 | 139 |
| 2014 | 10.07 | 127 |
| 2013 | 10.1 | 125 |
| 2012 | 10.1 | 125 |
| 2011 | 10.9 | 130 |
| 2010 | 10.84 | 134 |
| 2009 | 13.22 | 150 |
| 2008 | 16.06 | 167 |
| 2007 | 13.43 | 158 |
| 2006 | 12.12 | 148 |
| 2005 | 10.93 | 133 |
| 2004 | 9.85 | 119 |
| 2003 | 13 | 145 |
| 2002 | 17.01 | 163 |
| 2001 | 14.84 | 152 |
| 2000 | 19.1 | 170 |
| 1999 | 16.27 | 163 |
| 1998 | 13.77 | 148 |
| 1997 | 14.05 | 150 |
| 1996 | 14.33 | 146 |
| 1995 | 14.62 | 149 |
| 1994 | 14.9 | 148 |
| 1993 | 15.19 | 146 |
| 1992 | 15.47 | 153 |
| 1991 | 18.6 | 167 |