| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2012 | 30.45 | 48 |
| 2011 | 30.93 | 46 |
| 2010 | 29.94 | 46 |
| 2009 | 27.26 | 50 |
| 2008 | 27.48 | 51 |
| 2007 | 25.62 | 58 |
| 2006 | 25.05 | 60 |
| 2005 | 23.28 | 62 |
| 2004 | 21.05 | 63 |
| 2003 | 20.89 | 62 |
| 1995 | 36.38 | 26 |
| 1994 | 40.07 | 24 |
| 1993 | 30.7 | 28 |
| 1992 | 29.89 | 29 |
| 1991 | 28.53 | 30 |
| 1990 | 24.31 | 30 |
| 1989 | 28.76 | 27 |
| 1988 | 28.51 | 27 |
| 1987 | 28.63 | 24 |
| 1986 | 30.17 | 23 |