| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 2.69 | 8 |
| 2015 | 2.71 | 11 |
| 2014 | 2.73 | 11 |
| 2013 | 2.76 | 12 |
| 2012 | 2.8 | 11 |
| 2011 | 2.85 | 12 |
| 2010 | 2.9 | 14 |
| 2009 | 2.94 | 15 |
| 2008 | 2.95 | 14 |
| 2007 | 2.91 | 15 |
| 2006 | 2.84 | 14 |
| 2005 | 2.72 | 14 |
| 2004 | 2.61 | 18 |
| 2003 | 2.55 | 24 |
| 2002 | 2.58 | 23 |
| 2001 | 2.67 | 19 |
| 2000 | 2.86 | 15 |
| 1999 | 2.96 | 16 |
| 1998 | 2.62 | 24 |
| 1997 | 2.22 | 40 |
| 1996 | 1.58 | 67 |
| 1995 | 0.73 | 101 |
| 1994 | 0.02 | 137 |
| 1993 | -.12 | 151 |
| 1992 | 0.54 | 112 |
| 1991 | 1.77 | 61 |
| 1990 | 3.34 | 11 |
| 1989 | 4.82 | 5 |
| 1988 | 5.84 | 5 |
| 1987 | 6.02 | 5 |
| 1986 | 5.32 | 4 |