| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 55.4 | 110 |
| 2015 | 55.57 | 111 |
| 2014 | 55.83 | 112 |
| 2013 | 56.35 | 114 |
| 2012 | 57.12 | 118 |
| 2011 | 58.02 | 119 |
| 2010 | 58.88 | 119 |
| 2009 | 60.21 | 119 |
| 2008 | 61.89 | 121 |
| 2007 | 63.82 | 121 |
| 2006 | 65.84 | 123 |
| 2005 | 67.93 | 124 |
| 2004 | 69.92 | 126 |
| 2003 | 71.86 | 128 |
| 2002 | 74.07 | 128 |
| 2001 | 76.97 | 129 |
| 2000 | 80.74 | 137 |
| 1999 | 85.36 | 146 |
| 1998 | 90.22 | 160 |
| 1997 | 94.56 | 170 |
| 1996 | 97.31 | 177 |
| 1995 | 98.05 | 177 |
| 1994 | 98.23 | 175 |
| 1993 | 96.43 | 170 |
| 1992 | 93.41 | 157 |
| 1991 | 90.72 | 142 |
| 1990 | 89.34 | 136 |
| 1989 | 87.21 | 125 |
| 1988 | 86.56 | 125 |
| 1987 | 86.69 | 125 |
| 1986 | 85.81 | 123 |