| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 16.96 | 136 |
| 2015 | 16.05 | 136 |
| 2014 | 15.13 | 135 |
| 2013 | 14.26 | 134 |
| 2012 | 13.47 | 131 |
| 2011 | 12.79 | 129 |
| 2010 | 12.25 | 128 |
| 2009 | 12.13 | 129 |
| 2008 | 12.04 | 131 |
| 2007 | 11.89 | 133 |
| 2006 | 11.64 | 131 |
| 2005 | 11.33 | 131 |
| 2004 | 11.05 | 128 |
| 2003 | 10.87 | 126 |
| 2002 | 10.71 | 126 |
| 2001 | 10.52 | 126 |
| 2000 | 10.32 | 124 |
| 1999 | 9.98 | 122 |
| 1998 | 9.68 | 121 |
| 1997 | 9.4 | 118 |
| 1996 | 9.14 | 116 |
| 1995 | 8.89 | 116 |
| 1994 | 8.61 | 115 |
| 1993 | 8.33 | 113 |
| 1992 | 8.08 | 110 |
| 1991 | 7.86 | 109 |
| 1990 | 7.68 | 104 |
| 1989 | 7.62 | 101 |
| 1988 | 7.58 | 102 |
| 1987 | 7.56 | 102 |
| 1986 | 7.54 | 102 |