| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 78 | 169 |
| 2015 | 78.55 | 171 |
| 2014 | 79.22 | 171 |
| 2013 | 79.89 | 169 |
| 2012 | 80.52 | 169 |
| 2011 | 81.05 | 171 |
| 2010 | 81.43 | 171 |
| 2009 | 82.01 | 170 |
| 2008 | 82.53 | 171 |
| 2007 | 82.95 | 170 |
| 2006 | 83.26 | 170 |
| 2005 | 83.41 | 170 |
| 2004 | 83.88 | 170 |
| 2003 | 84.27 | 170 |
| 2002 | 84.53 | 168 |
| 2001 | 84.63 | 167 |
| 2000 | 84.51 | 165 |
| 1999 | 84.97 | 164 |
| 1998 | 85.26 | 162 |
| 1997 | 85.29 | 160 |
| 1996 | 85.03 | 159 |
| 1995 | 84.5 | 154 |
| 1994 | 84.88 | 153 |
| 1993 | 84.77 | 149 |
| 1992 | 84.39 | 143 |
| 1991 | 83.83 | 140 |
| 1990 | 83.06 | 137 |
| 1989 | 82.51 | 131 |
| 1988 | 82.07 | 131 |
| 1987 | 81.58 | 130 |
| 1986 | 80.87 | 129 |