| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 7.064 | 16 |
| 2015 | 5.937 | 29 |
| 2014 | 6.036 | 37 |
| 2013 | 5.414 | 57 |
| 2012 | 4.73 | 71 |
| 2011 | 6.085 | 55 |
| 2010 | 7.302 | 42 |
| 2009 | 6.226 | 31 |
| 2008 | 2.74 | 115 |
| 2007 | 7 | 81 |
| 2006 | 7.668 | 52 |
| 2005 | 4.59 | 96 |
| 2004 | 5.122 | 84 |
| 2003 | 2.531 | 116 |
| 2002 | 2.701 | 105 |
| 2001 | -.144 | 142 |
| 2000 | 1.876 | 132 |
| 1999 | 2.087 | 107 |
| 1998 | 2.248 | 111 |
| 1997 | 1.697 | 126 |
| 1996 | 5.177 | 56 |
| 1995 | 5.312 | 42 |
| 1994 | 3.442 | 67 |
| 1993 | 2.196 | 76 |
| 1992 | 2.922 | 71 |
| 1991 | 3.603 | 48 |
| 1990 | 4.477 | 49 |
| 1989 | 5.254 | 36 |
| 1988 | 5.419 | 36 |
| 1987 | 5.127 | 40 |
| 1986 | 6.661 | 22 |