| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 6.33 | 58 |
| 2015 | 6.34 | 61 |
| 2014 | 6.35 | 62 |
| 2013 | 6.35 | 63 |
| 2012 | 6.34 | 64 |
| 2011 | 6.33 | 64 |
| 2010 | 6.32 | 63 |
| 2009 | 6.28 | 63 |
| 2008 | 6.25 | 62 |
| 2007 | 6.21 | 63 |
| 2006 | 6.16 | 60 |
| 2005 | 6.11 | 60 |
| 2004 | 6.12 | 59 |
| 2003 | 6.14 | 58 |
| 2002 | 6.15 | 56 |
| 2001 | 6.16 | 55 |
| 2000 | 6.14 | 54 |
| 1999 | 6.17 | 54 |
| 1998 | 6.18 | 53 |
| 1997 | 6.17 | 52 |
| 1996 | 6.14 | 54 |
| 1995 | 6.13 | 53 |
| 1994 | 6.14 | 52 |
| 1993 | 6.18 | 54 |
| 1992 | 6.22 | 54 |
| 1991 | 6.24 | 56 |
| 1990 | 6.22 | 55 |
| 1989 | 6.21 | 53 |
| 1988 | 6.16 | 53 |
| 1987 | 6.08 | 52 |
| 1986 | 6 | 51 |