| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2015 | 3.2 | 69 |
| 2014 | 2.22 | 101 |
| 2013 | 10 | 22 |
| 2012 | 10.4 | 14 |
| 2011 | 7.9 | 34 |
| 2010 | 6.8 | 35 |
| 2009 | 10.5 | 21 |
| 2008 | 7.8 | 38 |
| 2007 | 6.5 | 41 |
| 2006 | 5.4 | 48 |
| 2005 | 1.4 | 96 |
| 2004 | 15.3 | 16 |
| 2003 | 10.4 | 20 |
| 2002 | 12.7 | 13 |
| 2001 | 6.61 | 42 |
| 2000 | 12.87 | 9 |
| 1999 | 3.1 | 81 |
| 1998 | 6.3 | 33 |
| 1997 | 3.6 | 59 |
| 1996 | -17.8 | 154 |
| 1995 | -13.4 | 132 |
| 1994 | -8.4 | 114 |
| 1993 | -4.4 | 104 |
| 1992 | -26.7 | 127 |
| 1991 | -4.4 | 107 |
| 1990 | -9.1 | 109 |
| 1989 | -13.1 | 108 |
| 1988 | 10.9 | 16 |
| 1987 | -6.4 | 93 |
| 1986 | 3.9 | 42 |