| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 6.42 | 25 |
| 2015 | 5.98 | 40 |
| 2014 | 9.84 | 18 |
| 2013 | 19.12 | 9 |
| 2012 | 19.17 | 5 |
| 2011 | 16.03 | 11 |
| 2010 | 7.42 | 60 |
| 2009 | 3.78 | 41 |
| 2008 | 16.87 | 11 |
| 2007 | 11.58 | 20 |
| 2006 | 9.06 | 47 |
| 2005 | 3.31 | 100 |
| 2004 | 6.57 | 64 |
| 2003 | 6.98 | 57 |
| 2002 | -.99 | 133 |
| 2001 | -9.91 | 161 |
| 2000 | -2.57 | 142 |
| 1999 | 10.67 | 18 |
| 1998 | 3.97 | 80 |
| 1997 | 5.77 | 65 |
| 1996 | 3.56 | 81 |
| 1995 | 1.4 | 95 |
| 1994 | 4.28 | 67 |
| 1993 | 15.26 | 6 |
| 1992 | 9.53 | 26 |
| 1991 | 14.51 | 11 |
| 1990 | 9.71 | 18 |
| 1989 | -3.76 | 103 |
| 1988 | -21.04 | 112 |
| 1987 | 1.59 | 74 |
| 1986 | 4.37 | 53 |