| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 29.03 | 54 |
| 2015 | 22.2 | 113 |
| 2014 | 21.35 | 118 |
| 2013 | 23.85 | 104 |
| 2012 | 26.15 | 94 |
| 2011 | 24.18 | 109 |
| 2010 | 22.67 | 116 |
| 2009 | 20.79 | 123 |
| 2008 | 20.61 | 135 |
| 2007 | 19.63 | 138 |
| 2006 | 16.98 | 149 |
| 2005 | 19.97 | 130 |
| 2004 | 26.97 | 90 |
| 2003 | 27.19 | 86 |
| 2002 | 28.58 | 77 |
| 2001 | 28.92 | 75 |
| 2000 | 29.04 | 76 |
| 1999 | 29.98 | 65 |
| 1998 | 30.79 | 58 |
| 1997 | 33.74 | 38 |
| 1996 | 33.8 | 40 |
| 1995 | 32.64 | 51 |
| 1994 | 36.66 | 31 |
| 1993 | 35.74 | 34 |
| 1992 | 29.02 | 68 |
| 1991 | 32.01 | 56 |
| 1990 | 24.88 | 85 |
| 1989 | 29.45 | 57 |
| 1988 | 29.61 | 54 |
| 1987 | 30.11 | 52 |
| 1986 | 27.11 | 58 |