| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 0.4 | 66 |
| 2015 | 2.3 | 103 |
| 2014 | 2.82 | 101 |
| 2013 | 2.55 | 103 |
| 2012 | 2.31 | 114 |
| 2011 | 2.3 | 116 |
| 2010 | 2.03 | 126 |
| 2009 | 0.9 | 149 |
| 2008 | 1.83 | 145 |
| 2007 | 1.6 | 158 |
| 2006 | 1.35 | 154 |
| 2005 | 2.92 | 101 |
| 2004 | 0.74 | 153 |
| 2003 | -.25 | 179 |
| 2002 | 0.07 | 172 |
| 2001 | -1.86 | 177 |
| 2000 | -2.76 | 175 |
| 1999 | -1.33 | 174 |
| 1998 | -.25 | 172 |
| 1997 | 2.17 | 88 |
| 1996 | 2.72 | 50 |
| 1995 | 2.15 | 62 |
| 1994 | 1.19 | 80 |
| 1993 | 1.27 | 70 |
| 1992 | 1.39 | 56 |
| 1991 | 1.27 | 53 |
| 1990 | 1.03 | 64 |
| 1989 | 0.72 | 67 |
| 1988 | 0.68 | 60 |
| 1987 | 0.51 | 75 |
| 1986 | 0.32 | 81 |