| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 80.09 | 40 |
| 2015 | 81.96 | 41 |
| 2014 | 82.18 | 49 |
| 2013 | 83.7 | 52 |
| 2012 | 84.7 | 55 |
| 2011 | 85.97 | 55 |
| 2010 | 79.85 | 59 |
| 2009 | 70.44 | 64 |
| 2008 | 85.49 | 57 |
| 2007 | 84.53 | 51 |
| 2006 | 81.95 | 56 |
| 2005 | 80.25 | 58 |
| 2004 | 79.46 | 50 |
| 2003 | 75.44 | 51 |
| 2002 | 73.71 | 57 |
| 2001 | 73.82 | 55 |
| 2000 | 71.33 | 63 |
| 1999 | 63.39 | 70 |
| 1998 | 61.37 | 71 |
| 1997 | 59.12 | 77 |
| 1996 | 53.53 | 89 |
| 1995 | 51.56 | 97 |
| 1994 | 49.37 | 89 |
| 1993 | 47.29 | 82 |
| 1992 | 50.69 | 72 |
| 1991 | 53.02 | 62 |
| 1990 | 54.44 | 63 |
| 1989 | 53.38 | 63 |
| 1988 | 50.56 | 69 |
| 1987 | 48.35 | 73 |
| 1986 | 49.97 | 66 |