| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 4.11 | 37 |
| 2015 | 3.72 | 57 |
| 2014 | 4.27 | 56 |
| 2013 | 2.94 | 89 |
| 2012 | 6.7 | 33 |
| 2011 | 2.92 | 106 |
| 2010 | 5.82 | 44 |
| 2009 | 5.88 | 40 |
| 2008 | 6.27 | 57 |
| 2007 | 7.19 | 33 |
| 2006 | 7.4 | 29 |
| 2005 | 7.06 | 36 |
| 2004 | 6.29 | 50 |
| 2003 | 6.98 | 37 |
| 2002 | 55.18 | 1 |
| 2001 | 3.88 | 63 |
| 2000 | 2.95 | 75 |
| 1999 | 5.29 | 55 |
| 1998 | 4.11 | 51 |
| 1997 | 4.29 | 50 |
| 1996 | 4.15 | 66 |
| 1995 | 3.65 | 63 |
| 1994 | 2.47 | 60 |
| 1993 | 1.4 | 71 |
| 1992 | 2.1 | 65 |
| 1991 | 3.75 | 42 |
| 1990 | 4.29 | 49 |
| 1989 | 5.37 | 35 |
| 1988 | 10.27 | 20 |
| 1987 | -3.5 | 85 |
| 1986 | 9.71 | 15 |