| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 6.79 | 94 |
| 2015 | 6.81 | 90 |
| 2014 | 6.82 | 93 |
| 2013 | 6.84 | 86 |
| 2012 | 6.87 | 88 |
| 2011 | 6.88 | 83 |
| 2010 | 6.89 | 78 |
| 2009 | 6.91 | 85 |
| 2008 | 6.92 | 99 |
| 2007 | 6.95 | 96 |
| 2006 | 6.99 | 88 |
| 2005 | 6.98 | 77 |
| 2004 | 7.01 | 79 |
| 2003 | 7.05 | 80 |
| 2002 | 6.99 | 82 |
| 2001 | 6.99 | 81 |
| 2000 | 7 | 85 |
| 1999 | 7.04 | 81 |
| 1998 | 6.99 | 81 |
| 1997 | 7.05 | 84 |
| 1996 | 6.96 | 81 |
| 1995 | 7.23 | 86 |
| 1994 | 7.15 | 82 |
| 1993 | 6.78 | 84 |
| 1992 | 6.92 | 84 |
| 1991 | 6.94 | 88 |