| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2015 | 18.08 | 134 |
| 2014 | 18.16 | 139 |
| 2013 | 19.61 | 133 |
| 2012 | 19.81 | 132 |
| 2011 | 20.54 | 132 |
| 2010 | 20.24 | 131 |
| 2009 | 19.56 | 134 |
| 2008 | 19.09 | 139 |
| 2007 | 18.12 | 147 |
| 2006 | 18.94 | 141 |
| 2005 | 19.16 | 135 |
| 2004 | 23.25 | 120 |
| 2003 | 22.01 | 128 |
| 2002 | 22.9 | 120 |
| 2001 | 23.54 | 117 |
| 2000 | 22.3 | 123 |
| 1999 | 22.11 | 123 |
| 1998 | 24.45 | 105 |
| 1997 | 24.98 | 103 |
| 1996 | 24.07 | 108 |
| 1995 | 24.31 | 108 |
| 1994 | 25.6 | 86 |
| 1993 | 25.88 | 82 |
| 1992 | 25.17 | 86 |
| 1991 | 24.26 | 90 |
| 1990 | 23.97 | 88 |
| 1989 | 24.1 | 77 |
| 1988 | 21.68 | 80 |
| 1987 | 21.22 | 79 |
| 1986 | 20.09 | 78 |