| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 5.66 | 38 |
| 2015 | 5.66 | 39 |
| 2014 | 5.76 | 41 |
| 2013 | 5.89 | 43 |
| 2012 | 6.05 | 50 |
| 2011 | 6.22 | 62 |
| 2010 | 6.39 | 65 |
| 2009 | 6.48 | 67 |
| 2008 | 6.55 | 68 |
| 2007 | 6.61 | 68 |
| 2006 | 6.65 | 69 |
| 2005 | 6.67 | 69 |
| 2004 | 6.69 | 69 |
| 2003 | 6.69 | 70 |
| 2002 | 6.67 | 69 |
| 2001 | 6.65 | 69 |
| 2000 | 6.62 | 68 |
| 1999 | 6.5 | 63 |
| 1998 | 6.38 | 60 |
| 1997 | 6.25 | 57 |
| 1996 | 6.13 | 52 |
| 1995 | 6 | 47 |
| 1994 | 5.92 | 43 |
| 1993 | 5.85 | 41 |
| 1992 | 5.79 | 40 |
| 1991 | 5.73 | 41 |
| 1990 | 5.65 | 39 |
| 1989 | 5.58 | 33 |
| 1988 | 5.51 | 28 |
| 1987 | 5.42 | 28 |
| 1986 | 5.32 | 26 |