| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 1.85 | 54 |
| 2015 | 3.61 | 40 |
| 2014 | 3.8 | 23 |
| 2013 | 4.28 | 38 |
| 2012 | 2.96 | 56 |
| 2011 | 3.53 | 53 |
| 2010 | 2.31 | 79 |
| 2009 | 1.99 | 39 |
| 2008 | 3.74 | 61 |
| 2007 | 2.43 | 91 |
| 2006 | 2.3 | 86 |
| 2005 | 1.54 | 112 |
| 2004 | 1.1 | 116 |
| 2003 | 0.07 | 110 |
| 2002 | 0.19 | 101 |
| 2001 | -.6 | 113 |
| 2000 | 0.38 | 95 |
| 1999 | 0.8 | 85 |
| 1998 | 3.22 | 61 |
| 1997 | 3.37 | 49 |
| 1996 | 1.25 | 92 |
| 1995 | 0.94 | 77 |
| 1994 | 0.92 | 69 |
| 1993 | 1.31 | 54 |
| 1992 | 1.53 | 51 |
| 1991 | 1.31 | 56 |
| 1990 | 1.37 | 43 |
| 1989 | -.19 | 66 |
| 1988 | -1.07 | 70 |
| 1987 | 1.09 | 53 |
| 1986 | 2.88 | 40 |