| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 13.76 | 32 |
| 2015 | 19.27 | 21 |
| 2014 | 11.25 | 62 |
| 2013 | 8.19 | 99 |
| 2012 | 6.2 | 112 |
| 2011 | 7.93 | 102 |
| 2010 | 10.97 | 91 |
| 2009 | 13.21 | 70 |
| 2008 | 9.43 | 113 |
| 2007 | 12.93 | 114 |
| 2006 | 12.25 | 122 |
| 2005 | 9.32 | 123 |
| 2004 | 14.78 | 75 |
| 2003 | 33.04 | 21 |
| 2002 | 7.3 | 109 |
| 2001 | -8.62 | 153 |
| 2000 | 10.82 | 96 |
| 1999 | 13.14 | 85 |
| 1998 | 8.49 | 94 |
| 1997 | 3.73 | 141 |
| 1996 | 11.69 | 93 |
| 1995 | 7.42 | 114 |
| 1994 | 38.69 | 35 |
| 1993 | -12.58 | 134 |
| 1992 | 3.59 | 109 |
| 1991 | 5.82 | 95 |
| 1990 | -4.81 | 119 |
| 1989 | 10.3 | 87 |
| 1988 | 0.5 | 115 |
| 1987 | -.25 | 113 |
| 1986 | 11.18 | 74 |