| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 1.21 | 86 |
| 2015 | 1.25 | 89 |
| 2014 | 1.25 | 93 |
| 2013 | 1.27 | 92 |
| 2012 | 1.41 | 76 |
| 2011 | 1.32 | 78 |
| 2010 | 1.38 | 84 |
| 2009 | 1.35 | 95 |
| 2008 | 1.36 | 95 |
| 2007 | 1.36 | 90 |
| 2006 | 1.36 | 97 |
| 2005 | 1.38 | 101 |
| 2004 | 1.43 | 92 |
| 2003 | 1.42 | 97 |
| 2002 | 1.46 | 91 |
| 2001 | 1.63 | 77 |
| 2000 | 1.73 | 72 |
| 1999 | 1.76 | 69 |
| 1998 | 1.67 | 77 |
| 1997 | 1.68 | 77 |
| 1996 | 1.76 | 71 |
| 1995 | 1.87 | 71 |
| 1994 | 1.91 | 73 |
| 1993 | 1.92 | 81 |
| 1992 | 1.95 | 79 |
| 1991 | 2.03 | 76 |
| 1990 | 2.19 | 72 |
| 1989 | 2.25 | 66 |
| 1988 | 2.37 | 63 |
| 1987 | 2.49 | 60 |
| 1986 | 2.5 | 57 |