| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 1.87 | 44 |
| 2015 | 1.91 | 51 |
| 2014 | 1.96 | 48 |
| 2013 | 1.99 | 49 |
| 2012 | 2.05 | 47 |
| 2011 | 2.25 | 38 |
| 2010 | 2.24 | 45 |
| 2009 | 2.26 | 46 |
| 2008 | 2.58 | 39 |
| 2007 | 2.32 | 41 |
| 2006 | 2.49 | 40 |
| 2005 | 2.52 | 38 |
| 2004 | 2.71 | 35 |
| 2003 | 2.73 | 36 |
| 2002 | 2.55 | 45 |
| 2001 | 2.67 | 45 |
| 2000 | 2.7 | 41 |
| 1999 | 2.72 | 42 |
| 1998 | 2.59 | 48 |
| 1997 | 2.5 | 49 |
| 1996 | 2.44 | 48 |
| 1995 | 2.49 | 49 |
| 1994 | 2.57 | 49 |
| 1993 | 2.62 | 53 |
| 1992 | 2.54 | 54 |
| 1991 | 2.74 | 51 |
| 1990 | 3.11 | 50 |
| 1989 | 3.31 | 43 |
| 1988 | 3.84 | 31 |
| 1987 | 5.24 | 19 |
| 1986 | 5.9 | 11 |