| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 7.56 | 5 |
| 2015 | 10.39 | 2 |
| 2014 | 10.26 | 2 |
| 2013 | 10.58 | 8 |
| 2012 | 8.65 | 16 |
| 2011 | 11.18 | 10 |
| 2010 | 12.55 | 7 |
| 2009 | 8.8 | 9 |
| 2008 | 10.79 | 8 |
| 2007 | 11.46 | 16 |
| 2006 | 10.83 | 15 |
| 2005 | 11.82 | 11 |
| 2004 | 13.57 | 8 |
| 2003 | -2.16 | 190 |
| 2002 | 1.51 | 139 |
| 2001 | 8.3 | 16 |
| 2000 | 6.07 | 44 |
| 1999 | 5.16 | 48 |
| 1998 | -3.46 | 184 |
| 1997 | 3.13 | 127 |
| 1996 | 12.43 | 5 |
| 1995 | 6.13 | 52 |
| 1994 | 3.19 | 105 |
| 1993 | 13.14 | 6 |
| 1992 | -8.67 | 161 |
| 1991 | -7.14 | 162 |
| 1990 | 2.73 | 94 |
| 1989 | -.36 | 140 |
| 1988 | 0.5 | 133 |
| 1987 | 13.86 | 6 |
| 1986 | 9.66 | 14 |