| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 4.33 | 45 |
| 2015 | 4.72 | 46 |
| 2014 | 3.66 | 85 |
| 2013 | 2.27 | 125 |
| 2012 | 4.8 | 66 |
| 2011 | 4.31 | 88 |
| 2010 | 4.95 | 84 |
| 2009 | -.97 | 113 |
| 2008 | 4.65 | 88 |
| 2007 | 8.17 | 52 |
| 2006 | 7.24 | 60 |
| 2005 | 3.87 | 123 |
| 2004 | 4.34 | 123 |
| 2003 | 4.26 | 93 |
| 2002 | 3.29 | 99 |
| 2001 | 3.49 | 89 |
| 2000 | 3.73 | 122 |
| 1999 | 3.94 | 76 |
| 1998 | 6.96 | 31 |
| 1997 | 5.56 | 65 |
| 1996 | 1.24 | 166 |
| 1995 | 4.12 | 93 |
| 1994 | 4.49 | 71 |
| 1993 | 7.09 | 25 |
| 1992 | 9.2 | 16 |
| 1991 | 2.57 | 80 |
| 1990 | 3.9 | 72 |
| 1989 | 5.07 | 52 |
| 1988 | 3.82 | 97 |
| 1987 | 6.88 | 37 |
| 1986 | 5.78 | 41 |