| 时间 | 值 | 世界排名 |
|---|---|---|
| 2015 | 10.3 | 16 |
| 2014 | 11.2 | 13 |
| 2013 | 9.2 | 18 |
| 2012 | 7.9 | 23 |
| 2011 | 8.8 | 17 |
| 2010 | 14.1 | 10 |
| 2009 | 12.8 | 13 |
| 2008 | 10 | 14 |
| 2007 | 8.7 | 19 |
| 2006 | 9.8 | 14 |
| 2005 | 8.4 | 16 |
| 2004 | 6.7 | 18 |
| 2003 | 5.9 | 35 |
| 2002 | 5.4 | 39 |
| 2001 | 5 | 35 |
| 2000 | 3.8 | 52 |
| 1999 | 3.3 | 65 |
| 1998 | 2.6 | 77 |
| 1997 | 2.4 | 90 |
| 1996 | 2.5 | 80 |
| 1995 | 1.8 | 100 |
| 1994 | 2.3 | 84 |
| 1993 | 1.5 | 100 |
| 1992 | 1.1 | 114 |
| 1991 | 1.9 | 80 |
| 1990 | 3.3 | 41 |
| 1989 | 1.7 | 85 |
| 1988 | 1 | 106 |
| 1987 | 1.4 | 97 |
| 1986 | 2.8 | 62 |