| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 3.09 | 52 |
| 2015 | 2.53 | 73 |
| 2014 | 1.51 | 93 |
| 2013 | 1.29 | 101 |
| 2012 | 1.11 | 105 |
| 2011 | 0.83 | 104 |
| 2010 | 1.31 | 99 |
| 2009 | 2.26 | 109 |
| 2008 | 1.34 | 118 |
| 2007 | 0.5 | 127 |
| 2006 | 1.61 | 109 |
| 2005 | 0.37 | 122 |
| 2004 | -.23 | 118 |
| 2003 | 0.67 | 110 |
| 2002 | 2.1 | 97 |
| 2001 | 0.17 | 118 |
| 2000 | -.91 | 112 |
| 1999 | 1.75 | 88 |
| 1998 | 3.79 | 49 |
| 1997 | -.46 | 106 |
| 1996 | -.13 | 102 |
| 1995 | 0.3 | 81 |
| 1994 | -1.06 | 87 |
| 1993 | 0.2 | 77 |
| 1992 | 2.33 | 57 |
| 1991 | 4.19 | 43 |
| 1990 | 2.74 | 47 |
| 1989 | 2.48 | 56 |
| 1988 | 0.88 | 62 |
| 1987 | 1.21 | 61 |
| 1986 | 1.68 | 60 |