| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 12.79 | 37 |
| 2015 | 1.17 | 133 |
| 2014 | 5.96 | 113 |
| 2013 | 19.04 | 26 |
| 2012 | 13.75 | 55 |
| 2011 | 9.56 | 91 |
| 2010 | 21.66 | 36 |
| 2009 | 2.66 | 132 |
| 2008 | 22.88 | 41 |
| 2007 | 24.12 | 53 |
| 2006 | 12.07 | 123 |
| 2005 | 17.1 | 67 |
| 2004 | 3.26 | 149 |
| 2003 | -2.14 | 155 |
| 2002 | 4.33 | 132 |
| 2001 | 0.56 | 147 |
| 2000 | -.4 | 148 |
| 1999 | 14.49 | 72 |
| 1998 | 17.33 | 43 |
| 1997 | 30.78 | 27 |
| 1996 | 37.24 | 25 |
| 1995 | 29.26 | 40 |
| 1994 | 37.22 | 38 |
| 1993 | 71.8 | 11 |
| 1992 | 88.18 | 8 |
| 1991 | 230.6 | 4 |
| 1990 | 6384.92 | 2 |
| 1989 | 1917.28 | 3 |
| 1988 | 620.95 | 3 |
| 1987 | 106.51 | 8 |
| 1986 | 53.98 | 14 |