| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 5.15 | 24 |
| 2015 | 5.1 | 23 |
| 2014 | 5.1 | 22 |
| 2013 | 5.13 | 21 |
| 2012 | 5.18 | 24 |
| 2011 | 5.24 | 25 |
| 2010 | 5.28 | 26 |
| 2009 | 5.35 | 27 |
| 2008 | 5.42 | 28 |
| 2007 | 5.48 | 29 |
| 2006 | 5.52 | 31 |
| 2005 | 5.56 | 31 |
| 2004 | 5.62 | 32 |
| 2003 | 5.67 | 36 |
| 2002 | 5.7 | 37 |
| 2001 | 5.72 | 38 |
| 2000 | 5.72 | 36 |
| 1999 | 5.76 | 38 |
| 1998 | 5.79 | 39 |
| 1997 | 5.8 | 37 |
| 1996 | 5.81 | 38 |
| 1995 | 5.8 | 39 |
| 1994 | 5.82 | 39 |
| 1993 | 5.85 | 40 |
| 1992 | 5.87 | 45 |
| 1991 | 5.89 | 45 |
| 1990 | 5.88 | 45 |
| 1989 | 5.95 | 47 |
| 1988 | 6 | 47 |
| 1987 | 6.05 | 49 |
| 1986 | 6.1 | 55 |