| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 4.477 | 115 |
| 2015 | 4.295 | 132 |
| 2014 | 4.268 | 141 |
| 2013 | 4.561 | 143 |
| 2012 | 4.984 | 140 |
| 2011 | 5.193 | 136 |
| 2010 | 5.422 | 127 |
| 2009 | 6.158 | 119 |
| 2008 | 7.613 | 117 |
| 2007 | 8.536 | 111 |
| 2006 | 8.579 | 104 |
| 2005 | 7.498 | 115 |
| 2004 | 5.637 | 137 |
| 2003 | 5.417 | 140 |
| 2002 | 6.482 | 134 |
| 2001 | 7.884 | 121 |
| 2000 | 8.867 | 120 |
| 1999 | 8.562 | 123 |
| 1998 | 8.933 | 121 |
| 1997 | 8.797 | 119 |
| 1996 | 8.771 | 118 |
| 1995 | 8.369 | 121 |
| 1994 | 7.608 | 118 |
| 1993 | 7.953 | 110 |
| 1992 | 7.995 | 104 |
| 1989 | 8.376 | 98 |
| 1988 | 6.724 | 100 |
| 1987 | 7.862 | 96 |
| 1986 | 8.628 | 88 |