| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 31.233 | 2 |
| 2015 | 24.916 | 5 |
| 2014 | 24.009 | 6 |
| 2013 | 17.149 | 20 |
| 2012 | 14.061 | 39 |
| 2011 | 14.088 | 39 |
| 2010 | 10.558 | 70 |
| 2009 | 15.655 | 37 |
| 2008 | 19.468 | 20 |
| 2007 | 11.052 | 78 |
| 2006 | 8.627 | 103 |
| 2005 | 6.163 | 131 |
| 2004 | 6.777 | 126 |
| 2003 | 19.146 | 29 |
| 2002 | 51.679 | 4 |
| 2001 | 27.705 | 17 |
| 2000 | 11.086 | 102 |
| 1999 | 11.04 | 108 |
| 1998 | 10.635 | 111 |
| 1997 | 9.243 | 115 |
| 1996 | 10.511 | 105 |
| 1995 | 17.847 | 57 |
| 1994 | 10.059 | 97 |