| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 0.173 | 136 |
| 2015 | 0.614 | 133 |
| 2014 | 1.656 | 117 |
| 2013 | 2.413 | 105 |
| 2012 | 3.084 | 97 |
| 2011 | 3.368 | 88 |
| 2010 | 4.076 | 72 |
| 2009 | 6.178 | 64 |
| 2008 | 4.445 | 95 |
| 2007 | 3.682 | 119 |
| 2006 | 3.173 | 117 |
| 2005 | 3.084 | 109 |
| 2004 | 3.05 | 103 |
| 2003 | 2.932 | 112 |
| 2002 | 2.803 | 117 |
| 2001 | 2.919 | 129 |
| 2000 | 3.102 | 130 |
| 1999 | 3.213 | 130 |
| 1998 | 2.998 | 141 |
| 1997 | 46.828 | 3 |
| 1996 | 74.681 | 3 |
| 1995 | 35.944 | 15 |
| 1994 | 51.135 | 9 |
| 1993 | 42.558 | 10 |
| 1992 | 45.01 | 11 |
| 1991 | 39.492 | 11 |