| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 10.95 | 60 |
| 2015 | 10.56 | 60 |
| 2014 | 10.18 | 60 |
| 2013 | 9.82 | 62 |
| 2012 | 9.49 | 63 |
| 2011 | 9.19 | 63 |
| 2010 | 8.91 | 63 |
| 2009 | 8.65 | 63 |
| 2008 | 8.42 | 62 |
| 2007 | 8.2 | 63 |
| 2006 | 7.98 | 63 |
| 2005 | 7.76 | 63 |
| 2004 | 7.53 | 66 |
| 2003 | 7.28 | 68 |
| 2002 | 7.03 | 72 |
| 2001 | 6.78 | 72 |
| 2000 | 6.54 | 73 |
| 1999 | 6.31 | 75 |
| 1998 | 6.09 | 76 |
| 1997 | 5.88 | 77 |
| 1996 | 5.67 | 77 |
| 1995 | 5.47 | 78 |
| 1994 | 5.26 | 78 |
| 1993 | 5.06 | 79 |
| 1992 | 4.87 | 83 |
| 1991 | 4.69 | 86 |
| 1990 | 4.52 | 86 |
| 1989 | 4.37 | 86 |
| 1988 | 4.25 | 89 |
| 1987 | 4.15 | 94 |
| 1986 | 4.06 | 97 |