| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 4.649 | 40 |
| 2015 | 8.021 | 14 |
| 2014 | 8.112 | 15 |
| 2013 | 9.732 | 7 |
| 2012 | 7.792 | 32 |
| 2011 | 7.39 | 33 |
| 2010 | 5.618 | 69 |
| 2009 | 6.865 | 21 |
| 2008 | 8.647 | 30 |
| 2007 | 7.665 | 69 |
| 2006 | 7.647 | 53 |
| 2005 | 9.906 | 22 |
| 2004 | 8.903 | 37 |
| 2003 | 3.767 | 91 |
| 2002 | 5.939 | 46 |
| 2001 | 5.808 | 40 |
| 2000 | 5.342 | 58 |
| 1999 | 7.685 | 21 |
| 1998 | 4.956 | 49 |
| 1997 | 7.524 | 31 |
| 1996 | 8.086 | 21 |
| 1995 | 8.83 | 17 |
| 1994 | 6.681 | 29 |
| 1993 | 6.845 | 28 |
| 1992 | 0.87 | 97 |
| 1991 | 7.472 | 18 |
| 1990 | 1.534 | 80 |
| 1989 | 14.313 | 4 |
| 1988 | 0.82 | 93 |
| 1987 | 3.273 | 68 |
| 1986 | 1.663 | 78 |