| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 2 | 113 |
| 2015 | 1.93 | 124 |
| 2014 | 3.57 | 89 |
| 2013 | 5 | 57 |
| 2012 | 3.87 | 86 |
| 2011 | 6.22 | 52 |
| 2010 | 15.24 | 4 |
| 2009 | -.6 | 108 |
| 2008 | 1.79 | 142 |
| 2007 | 9.11 | 36 |
| 2006 | 8.86 | 32 |
| 2005 | 7.49 | 45 |
| 2004 | 9.55 | 27 |
| 2003 | 4.44 | 89 |
| 2002 | 4.21 | 73 |
| 2001 | -.95 | 174 |
| 2000 | 8.9 | 19 |
| 1999 | 6.1 | 41 |
| 1998 | -2.23 | 179 |
| 1997 | 8.29 | 24 |
| 1996 | 7.53 | 33 |
| 1995 | 7.03 | 36 |
| 1994 | 10.93 | 7 |
| 1993 | 11.54 | 8 |
| 1992 | 7.09 | 35 |
| 1991 | 6.69 | 30 |
| 1990 | 10.04 | 13 |
| 1989 | 10.18 | 12 |
| 1988 | 11.12 | 16 |
| 1987 | 10.76 | 13 |
| 1986 | 1.33 | 119 |