| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 11.23 | 54 |
| 2015 | 11.68 | 63 |
| 2014 | 12.18 | 61 |
| 2013 | 10.27 | 73 |
| 2012 | 11.19 | 67 |
| 2011 | 11.62 | 66 |
| 2010 | 13.27 | 58 |
| 2009 | 14.4 | 56 |
| 2008 | 19.4 | 45 |
| 2007 | 21.6 | 43 |
| 2006 | 20.28 | 46 |
| 2005 | 18.58 | 55 |
| 2004 | 19.58 | 53 |
| 2003 | 16.59 | 58 |
| 2002 | 14.03 | 70 |
| 2001 | 17.31 | 57 |
| 2000 | 18.26 | 57 |
| 1999 | 19.18 | 55 |
| 1998 | 21.79 | 52 |
| 1997 | 18.93 | 58 |
| 1996 | 21.77 | 51 |
| 1995 | 15.24 | 75 |
| 1994 | 18.97 | 62 |
| 1993 | 15.04 | 72 |
| 1992 | 7.41 | 98 |
| 1991 | 15.27 | 71 |
| 1990 | 16.48 | 72 |
| 1989 | 14.93 | 68 |
| 1988 | 16.38 | 62 |
| 1987 | 14.41 | 65 |
| 1986 | 17.76 | 56 |