| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 28.25 | 15 |
| 2015 | 29.71 | 15 |
| 2014 | 30.81 | 15 |
| 2013 | 30.77 | 16 |
| 2012 | 30.58 | 18 |
| 2011 | 31.25 | 14 |
| 2010 | 31.92 | 14 |
| 2009 | 32.81 | 17 |
| 2008 | 32.34 | 16 |
| 2007 | 30.56 | 19 |
| 2006 | 34.41 | 15 |
| 2005 | 37.11 | 13 |
| 2004 | 38.68 | 10 |
| 2003 | 38.91 | 13 |
| 2002 | 40.9 | 11 |
| 2001 | 38.78 | 11 |
| 2000 | 39.54 | 12 |
| 1999 | 37.84 | 16 |
| 1998 | 35.58 | 21 |
| 1997 | 32.59 | 30 |
| 1996 | 34.69 | 28 |
| 1995 | 30.4 | 37 |
| 1994 | 25.08 | 44 |
| 1993 | 48.9 | 11 |
| 1992 | 38.82 | 19 |
| 1991 | 43.72 | 12 |
| 1990 | 45 | 13 |
| 1989 | 47.69 | 10 |
| 1988 | 50.02 | 7 |
| 1987 | 49.03 | 8 |
| 1986 | 43.12 | 9 |