| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 5.91 | 44 |
| 2015 | 5.77 | 42 |
| 2014 | 5.68 | 40 |
| 2013 | 5.63 | 37 |
| 2012 | 5.59 | 36 |
| 2011 | 5.55 | 34 |
| 2010 | 5.51 | 32 |
| 2009 | 5.53 | 31 |
| 2008 | 5.54 | 31 |
| 2007 | 5.53 | 32 |
| 2006 | 5.53 | 32 |
| 2005 | 5.53 | 30 |
| 2004 | 5.64 | 33 |
| 2003 | 5.75 | 39 |
| 2002 | 5.85 | 46 |
| 2001 | 5.94 | 48 |
| 2000 | 6 | 49 |
| 1999 | 6.18 | 55 |
| 1998 | 6.33 | 58 |
| 1997 | 6.44 | 63 |
| 1996 | 6.53 | 63 |
| 1995 | 6.6 | 67 |
| 1994 | 6.82 | 73 |
| 1993 | 7.02 | 79 |
| 1992 | 7.19 | 85 |
| 1991 | 7.34 | 91 |
| 1990 | 7.45 | 95 |
| 1989 | 7.59 | 99 |
| 1988 | 7.74 | 109 |
| 1987 | 7.89 | 112 |
| 1986 | 8.01 | 113 |