| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 6.43 | 96 |
| 2015 | 6.26 | 96 |
| 2014 | 6.09 | 96 |
| 2013 | 5.93 | 96 |
| 2012 | 5.78 | 97 |
| 2011 | 5.64 | 98 |
| 2010 | 5.5 | 98 |
| 2009 | 5.36 | 99 |
| 2008 | 5.23 | 100 |
| 2007 | 5.11 | 102 |
| 2006 | 5 | 102 |
| 2005 | 4.88 | 103 |
| 2004 | 4.77 | 108 |
| 2003 | 4.66 | 108 |
| 2002 | 4.55 | 111 |
| 2001 | 4.45 | 110 |
| 2000 | 4.34 | 109 |
| 1999 | 4.26 | 109 |
| 1998 | 4.17 | 110 |
| 1997 | 4.09 | 111 |
| 1996 | 4.01 | 111 |
| 1995 | 3.93 | 115 |
| 1994 | 3.88 | 118 |
| 1993 | 3.83 | 118 |
| 1992 | 3.78 | 118 |
| 1991 | 3.73 | 121 |
| 1990 | 3.68 | 122 |
| 1989 | 3.64 | 122 |
| 1988 | 3.6 | 121 |
| 1987 | 3.56 | 124 |
| 1986 | 3.52 | 122 |