| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 2.82 | 48 |
| 2015 | 2.72 | 70 |
| 2014 | 4.02 | 66 |
| 2013 | 3.81 | 76 |
| 2012 | 4.11 | 84 |
| 2011 | 3.41 | 129 |
| 2010 | 4.16 | 76 |
| 2009 | 5.3 | 56 |
| 2008 | 5.12 | 135 |
| 2007 | 3.97 | 110 |
| 2006 | 3.63 | 103 |
| 2005 | 3.99 | 93 |
| 2004 | 4.69 | 67 |
| 2003 | 4.55 | 71 |
| 2002 | 5.03 | 64 |
| 2001 | 6.36 | 52 |
| 2000 | 9.5 | 37 |
| 1999 | 16.59 | 23 |
| 1998 | 15.93 | 24 |
| 1997 | 20.63 | 22 |
| 1996 | 34.38 | 20 |
| 1995 | 35 | 28 |
| 1994 | 6.97 | 95 |
| 1993 | 9.75 | 69 |
| 1992 | 15.51 | 44 |
| 1991 | 22.66 | 36 |
| 1990 | 26.65 | 25 |
| 1989 | 20.01 | 30 |
| 1988 | 114.16 | 6 |
| 1987 | 131.83 | 5 |
| 1986 | 86.23 | 6 |