| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 0.89 | 77 |
| 2015 | 1.04 | 72 |
| 2014 | 1.18 | 62 |
| 2013 | 1.23 | 61 |
| 2012 | 1.14 | 67 |
| 2011 | 0.93 | 81 |
| 2010 | 0.66 | 96 |
| 2009 | 0.42 | 110 |
| 2008 | 0.17 | 127 |
| 2007 | -.08 | 138 |
| 2006 | -.33 | 148 |
| 2005 | -.59 | 164 |
| 2004 | -.86 | 171 |
| 2003 | -1.1 | 179 |
| 2002 | -1.29 | 184 |
| 2001 | -1.43 | 187 |
| 2000 | -1.55 | 188 |
| 1999 | -1.67 | 188 |
| 1998 | -1.77 | 189 |
| 1997 | -1.85 | 191 |
| 1996 | -1.92 | 191 |
| 1995 | -1.98 | 189 |
| 1994 | -2.01 | 190 |
| 1993 | -1.89 | 189 |
| 1992 | -1.79 | 189 |
| 1991 | -1.67 | 183 |
| 1990 | -1.56 | 186 |
| 1989 | -1.44 | 183 |
| 1988 | -1.35 | 181 |
| 1987 | -.86 | 169 |
| 1986 | -.82 | 172 |