| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 77.68 | 59 |
| 2015 | 76.82 | 62 |
| 2014 | 75.92 | 62 |
| 2013 | 74.96 | 62 |
| 2012 | 73.94 | 64 |
| 2011 | 72.87 | 67 |
| 2010 | 71.73 | 68 |
| 2009 | 70.57 | 69 |
| 2008 | 69.39 | 71 |
| 2007 | 68.17 | 74 |
| 2006 | 66.93 | 78 |
| 2005 | 65.67 | 83 |
| 2004 | 64.39 | 84 |
| 2003 | 63.08 | 87 |
| 2002 | 61.75 | 89 |
| 2001 | 60.41 | 91 |
| 2000 | 59.05 | 93 |
| 1999 | 58.15 | 96 |
| 1998 | 57.26 | 96 |
| 1997 | 56.37 | 98 |
| 1996 | 55.47 | 99 |
| 1995 | 54.56 | 100 |
| 1994 | 53.65 | 103 |
| 1993 | 52.74 | 105 |
| 1992 | 51.83 | 105 |
| 1991 | 50.92 | 106 |
| 1990 | 50 | 109 |
| 1989 | 49.09 | 109 |
| 1988 | 48.18 | 112 |
| 1987 | 47.26 | 113 |
| 1986 | 46.35 | 112 |