| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 10.68 | 106 |
| 2015 | 10.46 | 107 |
| 2014 | 10.25 | 108 |
| 2013 | 10.06 | 108 |
| 2012 | 9.9 | 107 |
| 2011 | 9.75 | 106 |
| 2010 | 9.62 | 106 |
| 2009 | 9.48 | 105 |
| 2008 | 9.36 | 103 |
| 2007 | 9.25 | 103 |
| 2006 | 9.15 | 103 |
| 2005 | 9.04 | 101 |
| 2004 | 8.86 | 100 |
| 2003 | 8.66 | 98 |
| 2002 | 8.46 | 98 |
| 2001 | 8.25 | 94 |
| 2000 | 8.04 | 94 |
| 1999 | 7.9 | 93 |
| 1998 | 7.76 | 92 |
| 1997 | 7.62 | 90 |
| 1996 | 7.47 | 91 |
| 1995 | 7.33 | 86 |
| 1994 | 7.24 | 86 |
| 1993 | 7.16 | 86 |
| 1992 | 7.09 | 83 |
| 1991 | 7.01 | 81 |
| 1990 | 6.93 | 84 |
| 1989 | 6.9 | 84 |
| 1988 | 6.86 | 83 |
| 1987 | 6.83 | 83 |
| 1986 | 6.79 | 79 |