| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 9.71 | 66 |
| 2015 | 9.41 | 67 |
| 2014 | 9.16 | 68 |
| 2013 | 8.93 | 67 |
| 2012 | 8.72 | 68 |
| 2011 | 8.5 | 68 |
| 2010 | 8.29 | 69 |
| 2009 | 8.06 | 69 |
| 2008 | 7.84 | 69 |
| 2007 | 7.63 | 69 |
| 2006 | 7.43 | 71 |
| 2005 | 7.24 | 71 |
| 2004 | 7.07 | 74 |
| 2003 | 6.92 | 73 |
| 2002 | 6.79 | 73 |
| 2001 | 6.66 | 73 |
| 2000 | 6.53 | 74 |
| 1999 | 6.44 | 73 |
| 1998 | 6.35 | 72 |
| 1997 | 6.26 | 72 |
| 1996 | 6.17 | 71 |
| 1995 | 6.08 | 71 |
| 1994 | 6.02 | 71 |
| 1993 | 5.97 | 71 |
| 1992 | 5.91 | 69 |
| 1991 | 5.85 | 69 |
| 1990 | 5.77 | 68 |
| 1989 | 5.73 | 65 |
| 1988 | 5.69 | 65 |
| 1987 | 5.64 | 65 |
| 1986 | 5.59 | 64 |