| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 5.67 | 33 |
| 2015 | 4.39 | 51 |
| 2014 | 2.37 | 77 |
| 2013 | 5.24 | 48 |
| 2012 | 5.75 | 51 |
| 2011 | 7.78 | 26 |
| 2010 | 12.5 | 10 |
| 2009 | 21.69 | 11 |
| 2008 | 5 | 59 |
| 2007 | 82.09 | 2 |
| 2006 | -4.91 | 139 |
| 2005 | 2.9 | 81 |
| 2004 | -6.66 | 135 |
| 2003 | 4.8 | 46 |
| 2002 | 9.89 | 21 |
| 2001 | 8.85 | 25 |
| 2000 | 12.36 | 13 |
| 1999 | 16.76 | 11 |
| 1998 | -7.4 | 125 |
| 1997 | 1.97 | 79 |
| 1996 | 25.16 | 7 |
| 1995 | -23.2 | 121 |
| 1994 | 71.6 | 1 |