| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 48.18 | 79 |
| 2015 | 46.07 | 96 |
| 2014 | 41.15 | 103 |
| 2013 | 38.21 | 105 |
| 2012 | 35.65 | 106 |
| 2011 | 35.92 | 115 |
| 2010 | 35.24 | 114 |
| 2009 | 33.68 | 116 |
| 2008 | 29.95 | 121 |
| 2007 | 30.31 | 121 |
| 2006 | 29.67 | 115 |
| 2005 | 28.16 | 115 |
| 2004 | 27.88 | 115 |
| 2003 | 25.85 | 116 |
| 2002 | 20.84 | 128 |
| 2001 | 20.19 | 127 |
| 2000 | 23.72 | 108 |
| 1999 | 22.51 | 110 |
| 1998 | 21.24 | 114 |
| 1997 | 21.3 | 117 |
| 1996 | 21.61 | 112 |
| 1995 | 20.59 | 111 |
| 1994 | 21.68 | 114 |
| 1993 | 20.93 | 114 |
| 1992 | 24.22 | 100 |
| 1991 | 23.45 | 97 |
| 1990 | 22.56 | 92 |
| 1989 | 23.54 | 89 |
| 1988 | 22.53 | 91 |
| 1987 | 21.97 | 94 |
| 1986 | 23 | 89 |