| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 3.842 | 49 |
| 2015 | 6.695 | 38 |
| 2014 | 13.126 | 8 |
| 2013 | 15.623 | 4 |
| 2012 | 16.733 | 3 |
| 2011 | 17.5 | 2 |
| 2010 | 17.5 | 2 |
| 2009 | 17.5 | 2 |
| 2008 | 17.5 | 3 |
| 2007 | 17.5 | 3 |
| 2006 | 17.5 | 3 |
| 2005 | 14.35 | 5 |
| 2004 | 8.85 | 30 |
| 2003 | 6.5 | 57 |
| 2002 | 7.4 | 55 |
| 2001 | 8.025 | 51 |
| 2000 | 7.5 | 71 |
| 1999 | 5.667 | 91 |
| 1998 | 6.375 | 95 |
| 1995 | 17.5 | 32 |
| 1994 | 18 | 29 |
| 1993 | 19.75 | 27 |
| 1992 | 23 | 21 |
| 1991 | 22 | 26 |
| 1990 | 21 | 23 |
| 1989 | 19.5 | 19 |
| 1988 | 16.833 | 18 |
| 1987 | 15 | 21 |