| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2010 | 36.19 | 110 |
| 2009 | 30.82 | 125 |
| 2008 | 24.29 | 133 |
| 2007 | 24.1 | 137 |
| 2006 | 20.09 | 143 |
| 2005 | 19.08 | 142 |
| 2004 | 20.58 | 132 |
| 2003 | 19.92 | 133 |
| 2002 | 19.96 | 130 |
| 2001 | 16.34 | 139 |
| 2000 | 16.54 | 140 |
| 1999 | 14.95 | 142 |
| 1998 | 20.51 | 117 |
| 1997 | 18.44 | 126 |
| 1996 | 14.19 | 136 |
| 1995 | 13.62 | 141 |
| 1994 | 14.99 | 127 |
| 1993 | 13.23 | 134 |
| 1992 | 9.47 | 134 |
| 1991 | 7.11 | 133 |
| 1990 | 7.24 | 126 |
| 1989 | 9.88 | 120 |