| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 2.94 | 61 |
| 2015 | 2.27 | 90 |
| 2014 | 2.14 | 107 |
| 2013 | 2.08 | 112 |
| 2012 | 2.465 | 115 |
| 2011 | 2.85 | 102 |
| 2010 | 3.853 | 78 |
| 2009 | 5.403 | 70 |
| 2008 | 8.167 | 46 |
| 2007 | 7.054 | 51 |
| 2006 | 4.93 | 71 |
| 2005 | 4.013 | 81 |
| 2004 | 4.631 | 70 |
| 2003 | 7.588 | 48 |
| 2002 | 8.017 | 46 |
| 2001 | 6.15 | 72 |
| 2000 | 6.53 | 80 |
| 1999 | 9.859 | 51 |
| 1998 | 11.917 | 48 |
| 1997 | 12 | 51 |
| 1996 | 11.083 | 59 |
| 1995 | 9.438 | 64 |
| 1994 | 7.535 | 75 |
| 1993 | 7.89 | 68 |
| 1992 | 10.493 | 49 |
| 1991 | 10.599 | 51 |
| 1990 | 8.741 | 58 |
| 1989 | 9.076 | 56 |
| 1988 | 6.74 | 68 |
| 1987 | 4.888 | 91 |
| 1986 | 7.59 | 60 |