| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 22.1 | 120 |
| 2015 | 25.77 | 131 |
| 2014 | 20.93 | 140 |
| 2013 | 20.51 | 144 |
| 2012 | 19.58 | 147 |
| 2011 | 19.12 | 149 |
| 2010 | 18.43 | 151 |
| 2009 | 17.84 | 152 |
| 2008 | 19.1 | 151 |
| 2007 | 18.48 | 153 |
| 2006 | 18.06 | 151 |
| 2005 | 15.5 | 156 |
| 2004 | 18.77 | 137 |
| 2003 | 18.23 | 136 |
| 2002 | 18.35 | 137 |
| 2001 | 17.86 | 135 |
| 2000 | 21.69 | 116 |
| 1999 | 17.2 | 129 |
| 1998 | 16.62 | 131 |
| 1997 | 15.41 | 132 |
| 1996 | 16.04 | 131 |
| 1995 | 15.69 | 132 |
| 1994 | 13.56 | 132 |
| 1993 | 14.07 | 132 |
| 1991 | 22.36 | 101 |
| 1990 | 21.82 | 97 |
| 1989 | 30.31 | 72 |
| 1988 | 32.85 | 63 |
| 1987 | 29.06 | 77 |
| 1986 | 31.33 | 66 |