| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 0.38 | 106 |
| 2015 | 0.45 | 102 |
| 2014 | 0.5 | 101 |
| 2013 | 0.48 | 104 |
| 2012 | 0.35 | 112 |
| 2011 | 0.17 | 120 |
| 2010 | -.05 | 135 |
| 2009 | -.23 | 145 |
| 2008 | -.38 | 153 |
| 2007 | -.43 | 151 |
| 2006 | -.4 | 153 |
| 2005 | -.38 | 154 |
| 2004 | -.34 | 150 |
| 2003 | -.2 | 146 |
| 2002 | 0.16 | 127 |
| 2001 | 1.01 | 82 |
| 2000 | 1.43 | 67 |
| 1999 | 1.83 | 47 |
| 1998 | 2.15 | 38 |
| 1997 | 2.3 | 35 |
| 1996 | 2.32 | 36 |
| 1995 | 2.28 | 38 |
| 1994 | 2.26 | 42 |
| 1993 | 2.33 | 41 |
| 1992 | 2.64 | 30 |
| 1991 | 3.18 | 13 |
| 1990 | 3.59 | 7 |
| 1989 | 3.94 | 6 |
| 1988 | 4.1 | 9 |
| 1987 | 3.95 | 10 |
| 1986 | 3.52 | 9 |