| 时间 | 值 | 世界排名 |
|---|---|---|
| 2016 | 0 | 137 |
| 2015 | 0 | 140 |
| 2014 | 0 | 142 |
| 2013 | 0 | 140 |
| 2012 | 0.3 | 134 |
| 2011 | 0.5 | 130 |
| 2010 | 0.6 | 124 |
| 2009 | 1.4 | 116 |
| 2008 | 1.6 | 115 |
| 2007 | 1.4 | 116 |
| 2006 | 1.6 | 114 |
| 2005 | 1.4 | 115 |
| 2004 | 1.3 | 121 |
| 2003 | 1.2 | 124 |
| 2002 | 1.2 | 124 |
| 2001 | 0.8 | 136 |
| 2000 | 0.8 | 137 |
| 1999 | 0.8 | 138 |
| 1998 | 3.5 | 119 |
| 1997 | 3.9 | 118 |
| 1996 | 3.5 | 116 |
| 1995 | 3.5 | 113 |
| 1994 | 3.3 | 116 |
| 1993 | 2.9 | 119 |
| 1992 | 1.6 | 122 |
| 1991 | 1.4 | 119 |
| 1990 | 0.9 | 123 |
| 1989 | 0.9 | 121 |
| 1988 | 0.7 | 123 |
| 1987 | 0.6 | 124 |
| 1986 | 0.6 | 124 |