| 时间 | 值 | 世界排名 |
|---|---|---|
| 2016 | 8.1 | 89 |
| 2015 | 7.8 | 87 |
| 2014 | 13.2 | 84 |
| 2013 | 8.9 | 88 |
| 2012 | 9.5 | 85 |
| 2011 | 7.1 | 89 |
| 2010 | 3.9 | 101 |
| 2009 | 2.6 | 104 |
| 2008 | 5.9 | 99 |
| 2007 | 5.4 | 99 |
| 2006 | 6.3 | 95 |
| 2005 | 6.1 | 94 |
| 2004 | 6.3 | 101 |
| 2003 | 7.6 | 99 |
| 2002 | 8.2 | 101 |
| 2001 | 7.4 | 104 |
| 2000 | 8.4 | 115 |
| 1999 | 8.4 | 112 |
| 1998 | 7.4 | 113 |
| 1997 | 0.8 | 138 |
| 1996 | 3.3 | 119 |
| 1995 | 3.2 | 115 |
| 1994 | 3 | 118 |
| 1993 | 3 | 117 |
| 1992 | 1.4 | 123 |
| 1991 | 1.2 | 120 |