| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 65.5 | 90 |
| 2015 | 65.5 | 93 |
| 2014 | 65.8 | 88 |
| 2013 | 66 | 89 |
| 2012 | 66.2 | 84 |
| 2011 | 66.5 | 81 |
| 2010 | 66.7 | 78 |
| 2009 | 66.8 | 73 |
| 2008 | 66.9 | 71 |
| 2007 | 66.9 | 65 |
| 2006 | 67 | 60 |
| 2005 | 67.1 | 55 |
| 2004 | 67.3 | 47 |
| 2003 | 67.5 | 43 |
| 2002 | 67.7 | 38 |
| 2001 | 68 | 31 |
| 2000 | 68.2 | 24 |
| 1999 | 68.2 | 20 |
| 1998 | 68.2 | 17 |
| 1997 | 68.1 | 18 |
| 1996 | 68.1 | 18 |
| 1995 | 68.1 | 17 |
| 1994 | 67.8 | 19 |
| 1993 | 67.6 | 21 |
| 1992 | 67.3 | 23 |
| 1991 | 67 | 24 |
| 1990 | 66.7 | 28 |
| 1989 | 66.4 | 33 |
| 1988 | 66.1 | 36 |
| 1987 | 65.8 | 41 |
| 1986 | 65.5 | 42 |