| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 4.6 | 18 |
| 2015 | 4.3 | 25 |
| 2014 | 5.13 | 11 |
| 2013 | 5.32 | 26 |
| 2012 | 6.35 | 22 |
| 2011 | 4.93 | 36 |
| 2010 | 4.84 | 38 |
| 2009 | -1.25 | 96 |
| 2008 | 6.77 | 26 |
| 2007 | 8.44 | 27 |
| 2006 | 4.64 | 55 |
| 2005 | 7.05 | 33 |
| 2004 | 7.73 | 30 |
| 2003 | 5.97 | 34 |
| 2002 | 1.73 | 78 |
| 2001 | 0.8 | 88 |
| 2000 | 10.45 | 10 |
| 1999 | 0.4 | 89 |
| 1998 | -12.46 | 125 |
| 1997 | 1.69 | 78 |
| 1996 | 4.18 | 50 |
| 1995 | 8.89 | 18 |
| 1994 | 6.7 | 14 |
| 1993 | 3.62 | 35 |
| 1992 | 1.99 | 42 |
| 1991 | 6.16 | 20 |
| 1990 | 8.77 | 8 |
| 1989 | 10.04 | 7 |
| 1988 | 8.46 | 6 |
| 1987 | -.91 | 63 |
| 1986 | -12.51 | 82 |