| 时间 | 值 | 世界排名 |
|---|---|---|
| 2015 | 8.4 | 22 |
| 2014 | 7.3 | 24 |
| 2013 | 6.6 | 34 |
| 2012 | 4.4 | 69 |
| 2011 | 6.5 | 34 |
| 2010 | 8.5 | 23 |
| 2009 | 8.5 | 28 |
| 2008 | 5.4 | 35 |
| 2007 | 5.8 | 40 |
| 2006 | 6.1 | 31 |
| 2005 | 5.3 | 32 |
| 2004 | 6.7 | 20 |
| 2003 | 8.7 | 12 |
| 2002 | 7.3 | 16 |
| 2001 | 5.8 | 18 |
| 2000 | 6.5 | 14 |
| 1999 | 6.1 | 20 |
| 1998 | 4.2 | 41 |
| 1997 | 5.2 | 25 |
| 1996 | 4.2 | 35 |
| 1995 | 5.2 | 24 |
| 1994 | 5 | 28 |
| 1993 | 4.8 | 29 |
| 1992 | 2.6 | 64 |
| 1991 | 3.4 | 48 |
| 1990 | 3.5 | 35 |
| 1989 | 2.9 | 57 |
| 1988 | 1.2 | 98 |
| 1987 | 2.7 | 62 |
| 1986 | 2.9 | 57 |