| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 65.7 | 85 |
| 2015 | 65.6 | 87 |
| 2014 | 65.6 | 92 |
| 2013 | 65.6 | 96 |
| 2012 | 65.5 | 96 |
| 2011 | 65.4 | 98 |
| 2010 | 65.2 | 101 |
| 2009 | 65 | 99 |
| 2008 | 64.8 | 100 |
| 2007 | 64.5 | 99 |
| 2006 | 64.2 | 97 |
| 2005 | 64.1 | 97 |
| 2004 | 64 | 93 |
| 2003 | 63.9 | 92 |
| 2002 | 64 | 84 |
| 2001 | 64.1 | 81 |
| 2000 | 64.2 | 76 |
| 1999 | 64.1 | 74 |
| 1998 | 64 | 71 |
| 1997 | 64 | 71 |
| 1996 | 64.2 | 67 |
| 1995 | 64.4 | 62 |
| 1994 | 64.7 | 58 |
| 1993 | 65.1 | 55 |
| 1992 | 65.5 | 52 |
| 1991 | 65.8 | 45 |
| 1990 | 66.2 | 38 |
| 1989 | 65.9 | 42 |
| 1988 | 65.6 | 44 |
| 1987 | 65.2 | 46 |
| 1986 | 64.9 | 50 |