| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 2.01 | 52 |
| 2015 | 1.67 | 78 |
| 2014 | 1.11 | 94 |
| 2013 | 1.42 | 86 |
| 2012 | 1.39 | 89 |
| 2011 | 2.11 | 83 |
| 2010 | 3.86 | 46 |
| 2009 | -.35 | 79 |
| 2008 | 0.61 | 96 |
| 2007 | 4.57 | 61 |
| 2006 | 4.04 | 61 |
| 2005 | 4.2 | 60 |
| 2004 | -.14 | 129 |
| 2003 | -1.04 | 122 |
| 2002 | 8.25 | 19 |
| 2001 | 4.87 | 29 |
| 2000 | 8.14 | 16 |
| 1999 | 10.92 | 5 |
| 1998 | -12.53 | 126 |
| 1997 | 3.16 | 52 |
| 1996 | 6.58 | 30 |
| 1995 | 9.4 | 15 |
| 1994 | 7.88 | 11 |
| 1993 | 5.71 | 22 |
| 1992 | 5.75 | 18 |
| 1991 | 7.81 | 14 |
| 1990 | 8.77 | 9 |
| 1989 | 9.64 | 8 |
| 1988 | 8.16 | 10 |
| 1987 | 7.36 | 12 |
| 1986 | 7.99 | 12 |