| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 12.61 | 38 |
| 2015 | -3 | 142 |
| 2014 | 10.44 | 72 |
| 2013 | 17.73 | 34 |
| 2012 | 25.83 | 13 |
| 2011 | 22.59 | 23 |
| 2010 | 14.52 | 67 |
| 2009 | 11.83 | 75 |
| 2008 | 2.29 | 152 |
| 2007 | 9.84 | 139 |
| 2006 | 24.51 | 50 |
| 2005 | 12.16 | 95 |
| 2004 | 8.87 | 116 |
| 2003 | 12.26 | 88 |
| 2002 | 8.09 | 104 |
| 2001 | 7.81 | 115 |
| 2000 | -1.37 | 150 |
| 1999 | 6.78 | 128 |
| 1998 | 3.13 | 124 |
| 1997 | 5.18 | 133 |
| 1996 | 7.04 | 119 |
| 1995 | 13.45 | 86 |
| 1994 | 12.7 | 92 |
| 1993 | 6.91 | 97 |
| 1992 | 21.1 | 51 |
| 1991 | 36.89 | 27 |
| 1990 | 26.37 | 35 |
| 1989 | 21.25 | 43 |
| 1988 | 40.08 | 17 |
| 1987 | 28.93 | 32 |
| 1986 | 19.73 | 44 |