| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 0.42 | 89 |
| 2015 | 6.5 | 31 |
| 2014 | 7.53 | 22 |
| 2013 | 6.61 | 35 |
| 2012 | 2.69 | 122 |
| 2011 | 16.5 | 12 |
| 2010 | 7.97 | 28 |
| 2009 | 6.9 | 44 |
| 2008 | 24.52 | 12 |
| 2007 | 10.18 | 25 |
| 2006 | 5.56 | 77 |
| 2005 | 4.35 | 87 |
| 2004 | 4.11 | 78 |
| 2003 | 2.97 | 93 |
| 2002 | 2.13 | 114 |
| 2001 | 6.92 | 48 |
| 2000 | 18.7 | 18 |
| 1999 | 37.03 | 14 |
| 1998 | 10.46 | 45 |
| 1997 | 23.44 | 19 |
| 1996 | 31.95 | 21 |