| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 3.95 | 59 |
| 2015 | 2.43 | 112 |
| 2014 | 3.4 | 91 |
| 2013 | 2.45 | 118 |
| 2012 | 2.25 | 118 |
| 2011 | 2.27 | 133 |
| 2010 | 1.53 | 159 |
| 2009 | -.3 | 105 |
| 2008 | -1.12 | 183 |
| 2007 | 2.89 | 162 |
| 2006 | 2.8 | 160 |
| 2005 | 3.3 | 138 |
| 2004 | 3.95 | 136 |
| 2003 | 4.56 | 86 |
| 2002 | 4.67 | 59 |
| 2001 | 3.45 | 90 |
| 2000 | 2.9 | 139 |
| 1999 | 5.45 | 44 |
| 1998 | 0.81 | 157 |
| 1997 | 2.04 | 148 |
| 1996 | 3.63 | 111 |
| 1995 | 4.74 | 75 |
| 1994 | 5.13 | 60 |
| 1993 | 6.4 | 34 |
| 1992 | 1.11 | 102 |
| 1991 | -1.09 | 138 |
| 1990 | 0.15 | 120 |
| 1989 | 0.15 | 136 |
| 1988 | -.36 | 142 |
| 1987 | 0.94 | 123 |
| 1986 | 2.71 | 98 |