| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 3.85 | 95 |
| 2015 | 3.61 | 117 |
| 2014 | 3.54 | 123 |
| 2013 | 3.52 | 126 |
| 2012 | 3.52 | 126 |
| 2011 | 3.35 | 127 |
| 2010 | 3.46 | 124 |
| 2009 | 3.52 | 124 |
| 2008 | 3.29 | 127 |
| 2007 | 3.32 | 130 |
| 2006 | 3.2 | 130 |
| 2005 | 3.37 | 130 |
| 2004 | 3.58 | 132 |
| 2003 | 3.59 | 132 |
| 2002 | 3.58 | 134 |
| 2001 | 3.67 | 131 |
| 2000 | 3.54 | 131 |
| 1999 | 3.95 | 125 |
| 1998 | 4.21 | 123 |
| 1997 | 4.37 | 124 |
| 1996 | 4.72 | 124 |
| 1995 | 4.37 | 128 |
| 1994 | 4.3 | 116 |
| 1993 | 4.48 | 113 |
| 1992 | 6.68 | 102 |
| 1991 | 7.52 | 98 |
| 1990 | 7.85 | 98 |
| 1989 | 7.75 | 89 |
| 1988 | 7.9 | 87 |
| 1987 | 9.68 | 83 |
| 1986 | 10.3 | 75 |