| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 0.49 | 175 |
| 2015 | 0.54 | 170 |
| 2014 | 0.57 | 162 |
| 2013 | 0.62 | 156 |
| 2012 | 0.61 | 156 |
| 2011 | 0.61 | 159 |
| 2010 | 0.6 | 165 |
| 2009 | 0.6 | 164 |
| 2008 | 0.56 | 172 |
| 2007 | 0.53 | 171 |
| 2006 | 0.47 | 172 |
| 2005 | 0.39 | 175 |
| 2004 | 0.36 | 173 |
| 2003 | 0.37 | 173 |
| 2002 | 0.41 | 173 |
| 2001 | 0.51 | 170 |
| 2000 | 0.62 | 164 |
| 1999 | 0.78 | 153 |
| 1998 | 0.93 | 145 |
| 1997 | 1.05 | 146 |
| 1996 | 1.25 | 142 |
| 1995 | 1.36 | 134 |
| 1994 | 1.55 | 125 |
| 1993 | 1.86 | 119 |
| 1992 | 2.36 | 107 |
| 1991 | 2.98 | 84 |
| 1990 | 3.71 | 70 |
| 1989 | 4.66 | 42 |
| 1988 | 5.61 | 27 |
| 1987 | 5.94 | 22 |
| 1986 | 5.99 | 26 |