| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 2.5 | 42 |
| 2015 | 0.93 | 102 |
| 2014 | 2.12 | 62 |
| 2013 | 1.04 | 94 |
| 2012 | 4.16 | 45 |
| 2011 | 3.33 | 58 |
| 2010 | 2.06 | 85 |
| 2009 | 3.7 | 25 |
| 2008 | 3.86 | 59 |
| 2007 | 5.03 | 57 |
| 2006 | 4.49 | 56 |
| 2005 | 2.91 | 86 |
| 2004 | 0.21 | 127 |
| 2003 | 0.44 | 105 |
| 2002 | 0.24 | 100 |
| 2001 | 2.05 | 63 |
| 2000 | 3.23 | 46 |
| 1999 | 2.73 | 59 |
| 1998 | 0.38 | 100 |
| 1997 | 2.26 | 70 |
| 1996 | 2.09 | 78 |
| 1995 | 1.34 | 70 |
| 1994 | 2.2 | 47 |
| 1993 | 0.89 | 62 |
| 1992 | 0.75 | 59 |
| 1991 | 2.25 | 41 |
| 1990 | 3.23 | 29 |
| 1989 | 1.77 | 50 |
| 1988 | 1.95 | 50 |
| 1987 | 2.96 | 32 |
| 1986 | -2.13 | 68 |