| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 1.596 | 90 |
| 2015 | 1.592 | 108 |
| 2014 | 1.229 | 128 |
| 2013 | 1.662 | 123 |
| 2012 | 3.156 | 94 |
| 2011 | 3.388 | 86 |
| 2010 | 3.22 | 100 |
| 2009 | 2.741 | 118 |
| 2008 | 4.49 | 92 |
| 2007 | 3.696 | 117 |
| 2006 | 5.294 | 64 |
| 2005 | 5.556 | 59 |
| 2004 | 6.178 | 52 |
| 2003 | 5.221 | 68 |
| 2002 | 4.608 | 86 |
| 2001 | 8.744 | 47 |
| 2000 | 8.305 | 61 |
| 1999 | 8.167 | 67 |
| 1998 | 12.106 | 47 |
| 1997 | 10.194 | 59 |
| 1996 | 9.683 | 67 |
| 1995 | 8.392 | 73 |
| 1994 | 10.539 | 51 |
| 1993 | 9.606 | 53 |
| 1992 | 14.275 | 38 |
| 1991 | 18.802 | 30 |
| 1990 | 19.538 | 25 |
| 1989 | 14.126 | 32 |
| 1988 | 11.315 | 37 |
| 1987 | 8.202 | 50 |
| 1986 | 11.253 | 31 |