| 时间 | 值 | 世界排名 |
|---|---|---|
| 2015 | 4.3 | 70 |
| 2014 | 4.2 | 68 |
| 2013 | 5.4 | 50 |
| 2012 | 5.5 | 47 |
| 2011 | 3.8 | 85 |
| 2010 | 4.7 | 79 |
| 2009 | 8.4 | 29 |
| 2008 | 7.9 | 19 |
| 2007 | 10.2 | 16 |
| 2006 | 12.1 | 10 |
| 2005 | 9.6 | 12 |
| 2004 | 8.7 | 13 |
| 2003 | 3.5 | 75 |
| 2002 | 4.9 | 49 |
| 2001 | 6.8 | 14 |
| 2000 | 7.9 | 6 |
| 1999 | 4.6 | 46 |
| 1998 | 5.5 | 23 |
| 1997 | 5.3 | 21 |
| 1996 | 3.6 | 48 |
| 1995 | 1.3 | 118 |
| 1994 | 1.6 | 100 |
| 1993 | 1.5 | 99 |
| 1992 | 1.2 | 111 |
| 1991 | 4.4 | 33 |
| 1990 | 5 | 19 |
| 1989 | 3.2 | 45 |
| 1988 | 1.5 | 90 |
| 1987 | 2.3 | 76 |
| 1986 | 3.2 | 48 |