| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 10.25 | 50 |
| 2015 | 9.042 | 69 |
| 2014 | 8.625 | 84 |
| 2013 | 8.5 | 91 |
| 2012 | 8.75 | 91 |
| 2011 | 9 | 86 |
| 2010 | 9.75 | 81 |
| 2009 | 11.375 | 73 |
| 2008 | 14.833 | 46 |
| 2007 | 13.167 | 60 |
| 2006 | 11.167 | 79 |
| 2005 | 10.625 | 84 |
| 2004 | 11.292 | 80 |
| 2003 | 14.625 | 65 |
| 2002 | 15.25 | 64 |
| 2001 | 13.25 | 77 |
| 2000 | 14 | 77 |
| 1999 | 17.417 | 63 |
| 1998 | 19.5 | 59 |
| 1997 | 19.5 | 55 |
| 1996 | 18.667 | 64 |
| 1995 | 17.054 | 58 |
| 1994 | 14.25 | 73 |
| 1993 | 14.346 | 70 |
| 1992 | 15.921 | 55 |
| 1991 | 16.017 | 49 |
| 1990 | 14.5 | 50 |
| 1989 | 14.497 | 50 |
| 1988 | 13.148 | 48 |
| 1987 | 11.868 | 57 |
| 1986 | 14.283 | 40 |