| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 65.4 | 93 |
| 2015 | 65.4 | 96 |
| 2014 | 65.6 | 95 |
| 2013 | 65.7 | 94 |
| 2012 | 65.9 | 90 |
| 2011 | 66 | 88 |
| 2010 | 66.2 | 88 |
| 2009 | 65.9 | 90 |
| 2008 | 65.7 | 91 |
| 2007 | 65.5 | 90 |
| 2006 | 65.4 | 89 |
| 2005 | 65.4 | 83 |
| 2004 | 64.7 | 87 |
| 2003 | 64 | 91 |
| 2002 | 63.3 | 93 |
| 2001 | 62.5 | 93 |
| 2000 | 61.5 | 97 |
| 1999 | 61.3 | 95 |
| 1998 | 61 | 94 |
| 1997 | 60.8 | 94 |
| 1996 | 60.5 | 93 |
| 1995 | 60.4 | 92 |
| 1994 | 59.9 | 93 |
| 1993 | 59.5 | 92 |
| 1992 | 59.2 | 92 |
| 1991 | 58.9 | 92 |
| 1990 | 58.6 | 92 |
| 1989 | 58.5 | 91 |
| 1988 | 58.3 | 91 |
| 1987 | 58.2 | 88 |
| 1986 | 58.2 | 85 |