| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2015 | 28.21 | 17 |
| 2014 | 26.96 | 20 |
| 2013 | 28.81 | 19 |
| 2012 | 30.58 | 17 |
| 2011 | 28.19 | 21 |
| 2010 | 26.54 | 26 |
| 2009 | 26.77 | 25 |
| 2008 | 28.01 | 21 |
| 2007 | 27.04 | 24 |
| 2006 | 24.45 | 33 |
| 2005 | 24.42 | 35 |
| 2004 | 23.71 | 38 |
| 2003 | 25.06 | 39 |
| 2002 | 24.95 | 37 |
| 2001 | 24.73 | 37 |
| 2000 | 25.89 | 38 |
| 1999 | 25.41 | 43 |
| 1998 | 26.97 | 41 |
| 1997 | 24.41 | 44 |
| 1996 | 24.56 | 44 |
| 1995 | 25.32 | 44 |