| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2015 | 10.62 | 63 |
| 2014 | 10.59 | 70 |
| 2013 | 14.83 | 49 |
| 2012 | 11.05 | 70 |
| 2011 | 16.14 | 50 |
| 2010 | 17.8 | 52 |
| 2009 | 18 | 41 |
| 2008 | 20.5 | 49 |
| 2007 | 22.27 | 57 |
| 2006 | 21.63 | 67 |
| 2005 | 15.6 | 80 |
| 2004 | 16.73 | 63 |
| 2003 | 13.03 | 83 |
| 2002 | 16.76 | 58 |
| 2001 | 14.32 | 83 |
| 2000 | 15.17 | 72 |
| 1999 | 17.15 | 59 |
| 1998 | 18.17 | 37 |
| 1997 | 17.66 | 74 |
| 1996 | 18.74 | 64 |
| 1995 | 11.01 | 92 |
| 1994 | 20.28 | 71 |
| 1993 | 17.01 | 70 |
| 1992 | 16.86 | 64 |
| 1991 | 18.32 | 59 |
| 1990 | 15.07 | 63 |
| 1989 | 15.73 | 66 |
| 1988 | 18.29 | 59 |
| 1987 | 16.32 | 60 |
| 1986 | 17.93 | 51 |