| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | -.29 | 124 |
| 2015 | 5.27 | 106 |
| 2014 | 7.35 | 100 |
| 2013 | 14.16 | 52 |
| 2012 | -2.04 | 149 |
| 2011 | 2.7 | 137 |
| 2010 | 9.22 | 105 |
| 2009 | 24.29 | 25 |
| 2008 | 21.09 | 45 |
| 2007 | 12.43 | 116 |
| 2006 | 12.84 | 117 |
| 2005 | 21.41 | 50 |
| 2004 | 10.46 | 101 |
| 2003 | 16.61 | 59 |
| 2002 | 8.59 | 99 |
| 2001 | 8.1 | 111 |
| 2000 | 7.62 | 116 |
| 1999 | 15.5 | 67 |
| 1998 | 6.32 | 106 |
| 1997 | 7.64 | 120 |
| 1996 | -.91 | 148 |
| 1995 | 5.73 | 122 |
| 1994 | 3.33 | 135 |
| 1993 | 4.51 | 113 |
| 1992 | 3.34 | 110 |
| 1991 | 15.8 | 70 |
| 1990 | 8.27 | 89 |
| 1989 | 16.55 | 63 |
| 1988 | 15.55 | 67 |
| 1987 | 15.66 | 66 |
| 1986 | 10.62 | 77 |