| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 2.634 | 64 |
| 2015 | 2.868 | 70 |
| 2014 | 3.482 | 69 |
| 2013 | 4.174 | 61 |
| 2012 | 3.788 | 76 |
| 2011 | 3.351 | 89 |
| 2010 | 3.114 | 102 |
| 2009 | 2.885 | 114 |
| 2008 | 3.81 | 110 |
| 2007 | 3.286 | 130 |
| 2006 | 4.434 | 87 |
| 2005 | 3.382 | 101 |
| 2004 | 3.458 | 96 |
| 2003 | 3.932 | 93 |
| 2002 | 4.856 | 84 |
| 2001 | 4.67 | 101 |
| 2000 | 4.339 | 111 |
| 1999 | 4.762 | 108 |
| 1998 | 5.271 | 104 |
| 1997 | 5.042 | 104 |
| 1996 | 5 | 112 |
| 1995 | 5 | 111 |
| 1994 | 4 | 111 |
| 1993 | 4 | 110 |
| 1992 | 4 | 105 |
| 1991 | 4 | 108 |
| 1990 | 4 | 107 |
| 1989 | 4 | 106 |
| 1988 | 4 | 99 |
| 1987 | 4 | 97 |
| 1986 | 4 | 97 |