| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 2.88 | 47 |
| 2015 | 1.88 | 81 |
| 2014 | 3.08 | 78 |
| 2013 | 3.13 | 82 |
| 2012 | 1.87 | 149 |
| 2011 | 1.92 | 164 |
| 2010 | -2.43 | 178 |
| 2009 | -4.86 | 176 |
| 2008 | 15.05 | 33 |
| 2007 | 13.76 | 11 |
| 2006 | 11.84 | 17 |
| 2005 | 8.81 | 43 |
| 2004 | 6.8 | 53 |
| 2003 | 2.26 | 105 |
| 2002 | 0.24 | 150 |
| 2001 | 1.47 | 142 |
| 2000 | 1.65 | 122 |
| 1999 | 2.18 | 103 |
| 1998 | 2.95 | 106 |
| 1997 | 4.83 | 86 |
| 1996 | 4.9 | 100 |
| 1995 | 2.96 | 124 |
| 1994 | 1.32 | 144 |
| 1993 | -.87 | 147 |
| 1992 | 3.06 | 110 |
| 1991 | 4.42 | 101 |
| 1990 | 3 | 115 |
| 1989 | 3.3 | 104 |
| 1988 | 4.6 | 83 |
| 1987 | 2.69 | 96 |
| 1986 | 0.76 | 108 |