| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 19.05 | 110 |
| 2015 | 19.09 | 131 |
| 2014 | 19.3 | 132 |
| 2013 | 20.06 | 130 |
| 2012 | 20.69 | 127 |
| 2011 | 21.04 | 129 |
| 2010 | 20.79 | 125 |
| 2009 | 20.98 | 121 |
| 2008 | 20.87 | 132 |
| 2007 | 21.82 | 121 |
| 2006 | 21.88 | 125 |
| 2005 | 19.09 | 136 |
| 2004 | 18.23 | 140 |
| 2003 | 17.58 | 148 |
| 2002 | 17.41 | 145 |
| 2001 | 17.22 | 142 |
| 2000 | 16.92 | 147 |
| 1999 | 16.8 | 142 |
| 1998 | 17.5 | 141 |
| 1997 | 17.77 | 138 |
| 1996 | 18.33 | 131 |
| 1995 | 16.02 | 140 |
| 1994 | 17.25 | 118 |
| 1993 | 16.89 | 114 |
| 1992 | 18.38 | 107 |
| 1991 | 19.67 | 103 |
| 1990 | 19.04 | 102 |
| 1989 | 19.03 | 91 |
| 1988 | 19.61 | 86 |
| 1987 | 18.49 | 87 |
| 1986 | 18.58 | 83 |