| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 4.26 | 17 |
| 2015 | 4.4 | 18 |
| 2014 | 4.54 | 18 |
| 2013 | 4.59 | 20 |
| 2012 | 4.54 | 21 |
| 2011 | 4.36 | 29 |
| 2010 | 4.15 | 31 |
| 2009 | 3.95 | 35 |
| 2008 | 3.82 | 41 |
| 2007 | 3.76 | 46 |
| 2006 | 3.79 | 45 |
| 2005 | 3.81 | 45 |
| 2004 | 3.86 | 45 |
| 2003 | 3.99 | 39 |
| 2002 | 4.07 | 36 |
| 2001 | 3.4 | 59 |
| 2000 | 3.82 | 43 |
| 1999 | 4.22 | 25 |
| 1998 | 4.54 | 20 |
| 1997 | 4.69 | 21 |
| 1996 | 4.72 | 19 |
| 1995 | 4.66 | 22 |
| 1994 | 4.65 | 27 |
| 1993 | 4.71 | 30 |
| 1992 | 4.7 | 35 |
| 1991 | 4.49 | 46 |
| 1990 | 4.9 | 35 |
| 1989 | 5.25 | 27 |
| 1988 | 5.41 | 30 |
| 1987 | 5.25 | 32 |
| 1986 | 4.83 | 48 |