| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 0.84 | 152 |
| 2015 | 0.78 | 155 |
| 2014 | 0.7 | 157 |
| 2013 | 0.67 | 152 |
| 2012 | 0.6 | 157 |
| 2011 | 0.6 | 162 |
| 2010 | 0.55 | 167 |
| 2009 | 0.54 | 168 |
| 2008 | 0.56 | 173 |
| 2007 | 0.62 | 166 |
| 2006 | 1.12 | 140 |
| 2005 | 1.64 | 119 |
| 2004 | 1.72 | 115 |
| 2003 | 2.23 | 90 |
| 2002 | 2.76 | 77 |
| 2001 | 2.85 | 75 |
| 2000 | 2 | 100 |
| 1999 | 1.34 | 128 |
| 1998 | 1.55 | 121 |
| 1997 | 7.21 | 3 |
| 1996 | 6.64 | 3 |
| 1995 | -.36 | 195 |
| 1994 | -.75 | 200 |
| 1993 | -.89 | 204 |
| 1992 | -.66 | 203 |
| 1991 | 0.42 | 180 |
| 1990 | 0.8 | 164 |
| 1989 | 0.46 | 183 |
| 1988 | 0.79 | 176 |
| 1987 | 0.9 | 174 |
| 1986 | 0.82 | 175 |