| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 9.65 | 64 |
| 2015 | 10.26 | 71 |
| 2014 | 11.33 | 66 |
| 2013 | 11.25 | 67 |
| 2012 | 11.83 | 64 |
| 2011 | 12.72 | 60 |
| 2010 | 12.31 | 64 |
| 2009 | 13.08 | 59 |
| 2008 | 13.24 | 60 |
| 2007 | 12.5 | 64 |
| 2006 | 12.37 | 69 |
| 2005 | 12.66 | 70 |
| 2004 | 13.31 | 71 |
| 2003 | 12.7 | 75 |
| 2002 | 13.15 | 74 |
| 2001 | 13.2 | 74 |
| 2000 | 13.97 | 71 |
| 1999 | 15.21 | 69 |
| 1998 | 14.76 | 71 |
| 1997 | 18.87 | 59 |
| 1996 | 20.62 | 55 |
| 1995 | 21.63 | 51 |
| 1994 | 22 | 52 |
| 1993 | 21.6 | 51 |
| 1992 | 21.82 | 51 |
| 1991 | 20.98 | 53 |
| 1990 | 21.9 | 52 |
| 1989 | 22.69 | 48 |
| 1988 | 22.96 | 46 |
| 1987 | 24.01 | 44 |
| 1986 | 23.95 | 40 |