| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 4.332 | 117 |
| 2015 | 4.693 | 124 |
| 2014 | 5.881 | 109 |
| 2013 | 6.888 | 104 |
| 2012 | 7.048 | 105 |
| 2011 | 6.833 | 106 |
| 2010 | 6.815 | 113 |
| 2009 | 7.493 | 111 |
| 2008 | 7.189 | 119 |
| 2007 | 6.741 | 136 |
| 2006 | 6.694 | 134 |
| 2005 | 7.093 | 120 |
| 2004 | 7.573 | 112 |
| 2003 | 6.948 | 120 |
| 2002 | 7.151 | 122 |
| 2001 | 7.52 | 126 |
| 2000 | 8 | 124 |
| 1999 | 8 | 125 |
| 1998 | 8 | 125 |
| 1997 | 8.083 | 122 |
| 1996 | 8.5 | 121 |
| 1995 | 8.5 | 119 |
| 1994 | 8.833 | 107 |
| 1993 | 9 | 104 |
| 1992 | 9 | 95 |
| 1991 | 9 | 93 |
| 1990 | 9 | 92 |
| 1989 | 9 | 91 |
| 1988 | 9 | 88 |
| 1987 | 9 | 84 |
| 1986 | 9 | 83 |