| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 8.54 | 113 |
| 2015 | 8.52 | 112 |
| 2014 | 8.45 | 109 |
| 2013 | 8.36 | 109 |
| 2012 | 8.18 | 108 |
| 2011 | 8.2 | 110 |
| 2010 | 8.23 | 103 |
| 2009 | 8.24 | 103 |
| 2008 | 8.28 | 124 |
| 2007 | 8.34 | 115 |
| 2006 | 8.42 | 113 |
| 2005 | 8.5 | 111 |
| 2004 | 8.48 | 103 |
| 2003 | 8.44 | 98 |
| 2002 | 0.49 | 1 |
| 2001 | 1.14 | 6 |
| 2000 | 1.13 | 5 |
| 1999 | 1.14 | 6 |
| 1998 | 1.13 | 7 |
| 1997 | 1.14 | 7 |
| 1996 | 1.14 | 9 |
| 1995 | 0.6 | 2 |
| 1994 | 1.35 | 10 |
| 1993 | 1.39 | 9 |
| 1992 | 1.06 | 6 |
| 1991 | 1.21 | 9 |