| 时间 | 值 | 世界排名 |
|---|---|---|
| 2016 | 6.4 | 19 |
| 2015 | 6.3 | 39 |
| 2014 | 4.7 | 56 |
| 2013 | 4.6 | 66 |
| 2012 | 4.2 | 79 |
| 2011 | 5 | 52 |
| 2010 | 7.4 | 30 |
| 2009 | 7.6 | 33 |
| 2008 | 6.1 | 30 |
| 2007 | 9.1 | 18 |
| 2006 | 9.9 | 13 |
| 2005 | 9.2 | 14 |
| 2004 | 10.6 | 6 |
| 2003 | 11.2 | 7 |
| 2002 | 9.8 | 8 |
| 2001 | 8.8 | 7 |
| 2000 | 5 | 30 |
| 1999 | 6.2 | 16 |
| 1998 | 5.1 | 30 |
| 1997 | 4.9 | 29 |
| 1996 | 4.5 | 31 |
| 1995 | 4.1 | 34 |
| 1994 | 5.7 | 21 |
| 1993 | 5.2 | 21 |
| 1992 | 4.8 | 25 |
| 1991 | 4.5 | 30 |
| 1990 | 3.2 | 45 |
| 1989 | 1.2 | 98 |
| 1988 | 1.5 | 88 |
| 1987 | 1.6 | 91 |
| 1986 | 1.1 | 98 |