| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 3.55 | 1 |
| 2015 | 3.71 | 2 |
| 2014 | 3.87 | 4 |
| 2013 | 4.02 | 4 |
| 2012 | 4.15 | 4 |
| 2011 | 4.25 | 3 |
| 2010 | 4.35 | 4 |
| 2009 | 4.44 | 5 |
| 2008 | 4.48 | 5 |
| 2007 | 4.48 | 4 |
| 2006 | 4.43 | 4 |
| 2005 | 4.33 | 4 |
| 2004 | 4.22 | 4 |
| 2003 | 4.13 | 6 |
| 2002 | 4.09 | 5 |
| 2001 | 4.07 | 3 |
| 2000 | 4.06 | 6 |
| 1999 | 4.03 | 5 |
| 1998 | 3.98 | 5 |
| 1997 | 3.87 | 5 |
| 1996 | 3.73 | 6 |
| 1995 | 3.57 | 9 |
| 1994 | 1.77 | 58 |
| 1993 | 1.7 | 61 |
| 1992 | 1.65 | 64 |
| 1991 | 1.63 | 68 |
| 1990 | 1.52 | 67 |
| 1989 | 1.43 | 83 |
| 1988 | 1.64 | 67 |
| 1987 | 2.32 | 48 |
| 1986 | 3.32 | 13 |