| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2013 | 12.84 | 128 |
| 2012 | 18.54 | 86 |
| 2011 | 12.9 | 132 |
| 2010 | 9.81 | 147 |
| 2009 | 8.86 | 154 |
| 2008 | 12.16 | 136 |
| 2007 | 8.59 | 149 |
| 2006 | 12.58 | 129 |
| 2005 | 12.63 | 124 |
| 2004 | 10.05 | 132 |
| 2003 | 12.01 | 114 |
| 2002 | 13.45 | 104 |
| 2001 | 13.84 | 96 |
| 2000 | 11.77 | 109 |
| 1999 | 13.82 | 87 |
| 1998 | 13.75 | 91 |
| 1997 | 11.53 | 99 |
| 1996 | 14.14 | 79 |
| 1995 | 13.72 | 80 |
| 1994 | 15.34 | 74 |
| 1993 | 15.9 | 67 |
| 1992 | 14.68 | 67 |
| 1991 | 16.33 | 57 |
| 1990 | 19.68 | 45 |
| 1989 | 14.94 | 59 |
| 1988 | 11.89 | 67 |
| 1987 | 10.17 | 78 |
| 1986 | 10.03 | 76 |