| 时间 | 值 | 世界排名 |
|---|---|---|
| 2016 | 0.6 | 68 |
| 2015 | 0.6 | 136 |
| 2014 | 0.5 | 141 |
| 2013 | 0.5 | 154 |
| 2012 | 0.7 | 156 |
| 2011 | 0.5 | 155 |
| 2010 | 0.5 | 156 |
| 2009 | 0.6 | 157 |
| 2008 | 0.4 | 151 |
| 2007 | 4.8 | 52 |
| 2006 | 5.9 | 33 |
| 2005 | 4.9 | 38 |
| 2004 | 5.2 | 40 |
| 2003 | 5.4 | 43 |
| 2002 | 5.8 | 33 |
| 2001 | 4.6 | 39 |
| 2000 | 3.6 | 57 |
| 1999 | 4.1 | 49 |
| 1998 | 3.7 | 51 |
| 1997 | 3.4 | 59 |
| 1996 | 3.6 | 47 |
| 1995 | 2.9 | 59 |
| 1994 | 5.2 | 26 |
| 1993 | 4.6 | 32 |
| 1992 | 3.2 | 50 |
| 1991 | 5.3 | 19 |
| 1990 | 6 | 15 |
| 1989 | 5.4 | 14 |
| 1988 | 5.5 | 13 |
| 1987 | 6.6 | 14 |
| 1986 | 6.9 | 11 |