| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 5.68 | 39 |
| 2015 | 5.63 | 38 |
| 2014 | 5.65 | 38 |
| 2013 | 5.7 | 40 |
| 2012 | 5.77 | 41 |
| 2011 | 5.82 | 40 |
| 2010 | 5.85 | 42 |
| 2009 | 5.94 | 50 |
| 2008 | 6.01 | 51 |
| 2007 | 6.06 | 52 |
| 2006 | 6.08 | 57 |
| 2005 | 6.09 | 59 |
| 2004 | 6.22 | 63 |
| 2003 | 6.33 | 63 |
| 2002 | 6.42 | 63 |
| 2001 | 6.48 | 64 |
| 2000 | 6.52 | 65 |
| 1999 | 6.6 | 67 |
| 1998 | 6.67 | 68 |
| 1997 | 6.72 | 69 |
| 1996 | 6.74 | 71 |
| 1995 | 6.74 | 71 |
| 1994 | 6.7 | 68 |
| 1993 | 6.66 | 68 |
| 1992 | 6.63 | 68 |
| 1991 | 6.59 | 69 |
| 1990 | 6.56 | 69 |
| 1989 | 6.51 | 68 |
| 1988 | 6.45 | 65 |
| 1987 | 6.37 | 64 |
| 1986 | 6.28 | 62 |