| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 5.45 | 83 |
| 2015 | 4.97 | 102 |
| 2014 | 5.03 | 106 |
| 2013 | 5.28 | 109 |
| 2012 | 4.9 | 109 |
| 2011 | 5.11 | 109 |
| 2010 | 4.84 | 109 |
| 2009 | 5.24 | 110 |
| 2008 | 5.41 | 109 |
| 2007 | 5.18 | 112 |
| 2006 | 5.14 | 113 |
| 2005 | 5.48 | 109 |
| 2004 | 6.67 | 104 |
| 2003 | 7.2 | 101 |
| 2002 | 6.42 | 108 |
| 2001 | 5.64 | 115 |
| 2000 | 5.52 | 116 |
| 1999 | 5.37 | 114 |
| 1998 | 5.4 | 117 |
| 1997 | 5.33 | 116 |
| 1996 | 5.45 | 116 |
| 1995 | 5.77 | 118 |
| 1994 | 9.85 | 89 |
| 1993 | 7.56 | 99 |
| 1992 | 7.72 | 96 |
| 1991 | 7.79 | 97 |
| 1990 | 8.1 | 97 |
| 1989 | 8.52 | 88 |
| 1988 | 10.12 | 81 |
| 1987 | 10.01 | 80 |
| 1986 | 11.16 | 74 |