| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 3.5 | 48 |
| 2015 | 4.6 | 48 |
| 2014 | 3.88 | 56 |
| 2013 | 1.59 | 92 |
| 2012 | 2.84 | 81 |
| 2011 | 5.55 | 41 |
| 2010 | 2.56 | 76 |
| 2009 | 1.69 | 115 |
| 2008 | 0.72 | 129 |
| 2007 | 7.26 | 43 |
| 2006 | 5.05 | 68 |
| 2005 | 5.35 | 50 |
| 2004 | 5.6 | 41 |
| 2003 | 2.7 | 79 |
| 2002 | 3.55 | 67 |
| 2001 | 1.08 | 109 |
| 2000 | 0.16 | 105 |
| 1999 | 8.72 | 21 |
| 1998 | 0.98 | 97 |
| 1997 | 3.35 | 54 |
| 1996 | 2.11 | 76 |
| 1995 | 0.8 | 75 |
| 1994 | -3.68 | 102 |
| 1993 | -1.34 | 92 |
| 1992 | 0.24 | 74 |
| 1991 | -1.47 | 92 |
| 1990 | 0.7 | 65 |
| 1989 | 1.51 | 63 |
| 1988 | 1.72 | 53 |
| 1987 | 4.54 | 34 |
| 1986 | 2.08 | 57 |