| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 19.31 | 12 |
| 2015 | 18.88 | 12 |
| 2014 | 18.57 | 11 |
| 2013 | 18.25 | 12 |
| 2012 | 17.95 | 12 |
| 2011 | 17.71 | 12 |
| 2010 | 17.56 | 10 |
| 2009 | 17.43 | 10 |
| 2008 | 17.41 | 9 |
| 2007 | 17.44 | 9 |
| 2006 | 17.41 | 7 |
| 2005 | 17.25 | 9 |
| 2004 | 17.09 | 8 |
| 2003 | 16.79 | 9 |
| 2002 | 16.4 | 10 |
| 2001 | 15.97 | 11 |
| 2000 | 15.57 | 12 |
| 1999 | 15.23 | 14 |
| 1998 | 14.88 | 16 |
| 1997 | 14.51 | 18 |
| 1996 | 14.12 | 19 |
| 1995 | 13.69 | 21 |
| 1994 | 13.26 | 23 |
| 1993 | 12.83 | 25 |
| 1992 | 12.41 | 26 |
| 1991 | 11.99 | 26 |
| 1990 | 11.58 | 27 |
| 1989 | 11.33 | 27 |
| 1988 | 11.08 | 26 |
| 1987 | 10.87 | 26 |
| 1986 | 10.72 | 27 |