| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 54.25 | 134 |
| 2015 | 55.33 | 135 |
| 2014 | 56.43 | 135 |
| 2013 | 57.71 | 136 |
| 2012 | 59.15 | 136 |
| 2011 | 60.67 | 137 |
| 2010 | 62.27 | 138 |
| 2009 | 63.37 | 138 |
| 2008 | 64.47 | 137 |
| 2007 | 65.57 | 137 |
| 2006 | 66.7 | 137 |
| 2005 | 67.84 | 135 |
| 2004 | 68.88 | 137 |
| 2003 | 69.87 | 135 |
| 2002 | 70.78 | 134 |
| 2001 | 71.55 | 133 |
| 2000 | 72.05 | 129 |
| 1999 | 74.41 | 133 |
| 1998 | 76.73 | 137 |
| 1997 | 78.83 | 143 |
| 1996 | 80.6 | 145 |
| 1995 | 82.26 | 146 |
| 1994 | 83.5 | 146 |
| 1993 | 84.09 | 145 |
| 1992 | 84.12 | 141 |
| 1991 | 84.07 | 142 |
| 1990 | 84.31 | 144 |
| 1989 | 85.1 | 143 |
| 1988 | 86.28 | 144 |
| 1987 | 87.71 | 149 |
| 1986 | 88.9 | 152 |