| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 29.26 | 4 |
| 2015 | 30.16 | 5 |
| 2014 | 29.81 | 4 |
| 2013 | 29.45 | 4 |
| 2012 | 29.19 | 4 |
| 2011 | 29.02 | 4 |
| 2010 | 28.85 | 4 |
| 2009 | 30.09 | 4 |
| 2008 | 31.59 | 4 |
| 2007 | 33.45 | 4 |
| 2006 | 35.81 | 5 |
| 2005 | 38.74 | 8 |
| 2004 | 40.15 | 9 |
| 2003 | 41.76 | 11 |
| 2002 | 43.66 | 14 |
| 2001 | 45.89 | 19 |
| 2000 | 48.36 | 39 |
| 1999 | 47.96 | 35 |
| 1998 | 47.76 | 28 |
| 1997 | 47.87 | 24 |
| 1996 | 48.24 | 27 |
| 1995 | 48.47 | 28 |
| 1994 | 49.65 | 32 |
| 1993 | 50.97 | 42 |
| 1992 | 52.19 | 49 |
| 1991 | 53.11 | 53 |
| 1990 | 53.55 | 54 |
| 1989 | 54.47 | 54 |
| 1988 | 55.2 | 57 |
| 1987 | 55.88 | 58 |
| 1986 | 56.47 | 58 |