| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2015 | -.21 | 115 |
| 2014 | -2.41 | 143 |
| 2013 | 5.05 | 30 |
| 2012 | 2.12 | 77 |
| 2011 | 5.34 | 33 |
| 2010 | 5.61 | 30 |
| 2009 | -1.08 | 90 |
| 2008 | 2 | 81 |
| 2007 | 12.62 | 17 |
| 2006 | 8.55 | 25 |
| 2005 | 6.85 | 37 |
| 2004 | 5.47 | 45 |
| 2003 | 5.64 | 37 |
| 2002 | 16.02 | 6 |
| 2001 | 0.62 | 95 |
| 2000 | 6.63 | 21 |
| 1999 | 6.08 | 18 |
| 1998 | 39.39 | 2 |
| 1997 | 22.27 | 3 |
| 1996 | 10.47 | 12 |
| 1995 | 7.64 | 21 |
| 1994 | 3.52 | 36 |
| 1993 | 7.76 | 12 |
| 1992 | 6.41 | 15 |
| 1991 | 19.7 | 3 |
| 1990 | 4.75 | 20 |
| 1989 | 15.51 | 5 |
| 1988 | 21.87 | 1 |
| 1987 | 2.52 | 35 |
| 1986 | 12.36 | 8 |