| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 2.78 | 61 |
| 2015 | 3.13 | 55 |
| 2014 | 3.47 | 45 |
| 2013 | 3.72 | 41 |
| 2012 | 3.83 | 37 |
| 2011 | 3.82 | 39 |
| 2010 | 3.76 | 42 |
| 2009 | 3.71 | 42 |
| 2008 | 3.66 | 48 |
| 2007 | 3.61 | 52 |
| 2006 | 3.56 | 53 |
| 2005 | 3.5 | 52 |
| 2004 | 3.43 | 56 |
| 2003 | 3.38 | 58 |
| 2002 | 3.4 | 59 |
| 2001 | 3.45 | 58 |
| 2000 | 3.53 | 54 |
| 1999 | 3.61 | 55 |
| 1998 | 3.71 | 48 |
| 1997 | 3.82 | 48 |
| 1996 | 3.95 | 47 |
| 1995 | 4.09 | 41 |
| 1994 | 4.25 | 36 |
| 1993 | 4.36 | 39 |
| 1992 | 4.48 | 39 |
| 1991 | 4.58 | 42 |
| 1990 | 4.7 | 42 |
| 1989 | 4.81 | 37 |
| 1988 | 4.92 | 41 |
| 1987 | 4.76 | 49 |
| 1986 | 4.8 | 50 |