| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 0.75 | 78 |
| 2015 | 0.13 | 131 |
| 2014 | 2.64 | 90 |
| 2013 | 4.03 | 73 |
| 2012 | 5.7 | 60 |
| 2011 | 5.88 | 68 |
| 2010 | 3.49 | 90 |
| 2009 | 2.41 | 102 |
| 2008 | 8.76 | 91 |
| 2007 | 4.17 | 108 |
| 2006 | 2.1 | 146 |
| 2005 | 3.18 | 110 |
| 2004 | 0.18 | 162 |
| 2003 | 0.39 | 154 |
| 2002 | 1.01 | 140 |
| 2001 | 0.31 | 157 |
| 2000 | 1.5 | 128 |
| 1999 | 1.25 | 118 |
| 1998 | 0.56 | 147 |
| 1997 | 1.32 | 144 |
| 1996 | 1.26 | 149 |
| 1995 | 0.99 | 155 |
| 1994 | 1.27 | 145 |
| 1993 | 0.45 | 142 |
| 1992 | 1.82 | 121 |
| 1991 | 1.26 | 128 |
| 1990 | 0.77 | 128 |
| 1989 | 0.21 | 127 |
| 1988 | 0.36 | 122 |
| 1987 | 1 | 105 |
| 1986 | -.07 | 118 |