| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 23.64 | 31 |
| 2015 | 23.52 | 32 |
| 2014 | 23.94 | 34 |
| 2013 | 24.4 | 38 |
| 2012 | 24.87 | 38 |
| 2011 | 25.35 | 40 |
| 2010 | 25.81 | 42 |
| 2009 | 26.15 | 42 |
| 2008 | 26.52 | 40 |
| 2007 | 26.94 | 42 |
| 2006 | 27.38 | 42 |
| 2005 | 27.81 | 39 |
| 2004 | 28.01 | 38 |
| 2003 | 28.17 | 37 |
| 2002 | 28.26 | 33 |
| 2001 | 28.3 | 31 |
| 2000 | 28.28 | 27 |
| 1999 | 28.2 | 25 |
| 1998 | 28.07 | 22 |
| 1997 | 27.9 | 19 |
| 1996 | 27.63 | 19 |
| 1995 | 27.25 | 18 |
| 1994 | 26.79 | 11 |
| 1993 | 26.29 | 8 |
| 1992 | 25.81 | 8 |
| 1991 | 25.4 | 7 |
| 1990 | 25.06 | 6 |
| 1989 | 24.78 | 4 |
| 1988 | 24.59 | 3 |
| 1987 | 24.5 | 3 |
| 1986 | 24.55 | 3 |