| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 14.14 | 30 |
| 2015 | 11.78 | 55 |
| 2014 | 16.19 | 26 |
| 2013 | 14.15 | 53 |
| 2012 | 4.9 | 120 |
| 2011 | 37.15 | 6 |
| 2010 | 16.25 | 57 |
| 2009 | 62.57 | 1 |
| 2008 | 66.16 | 1 |
| 2007 | 38.55 | 25 |
| 2006 | 57.34 | 7 |
| 2005 | 60.54 | 2 |
| 2004 | 36.97 | 13 |
| 2003 | 66.31 | 3 |
| 2002 | 158.55 | 2 |
| 2001 | 161.22 | 3 |
| 2000 | 303.74 | 1 |
| 1999 | 528.19 | 1 |
| 1998 | 57.65 | 7 |
| 1997 | 71.94 | 7 |
| 1996 | 4105.57 | 1 |