| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 31.55 | 122 |
| 2015 | 30.93 | 120 |
| 2014 | 30.32 | 122 |
| 2013 | 30.76 | 121 |
| 2012 | 30.46 | 125 |
| 2011 | 30.5 | 125 |
| 2010 | 32.24 | 120 |
| 2009 | 32.46 | 121 |
| 2008 | 31.33 | 134 |
| 2007 | 31.98 | 131 |
| 2006 | 32.49 | 130 |
| 2005 | 31.27 | 134 |
| 2004 | 32.19 | 131 |
| 2003 | 32.88 | 127 |
| 2002 | 32.52 | 127 |
| 2001 | 32.49 | 132 |
| 2000 | 32.42 | 131 |
| 1999 | 33.27 | 128 |
| 1998 | 34.07 | 131 |
| 1997 | 34.67 | 130 |
| 1996 | 34.89 | 134 |
| 1995 | 31.87 | 144 |
| 1994 | 34.71 | 134 |
| 1993 | 33.56 | 141 |
| 1992 | 31.78 | 148 |
| 1991 | 29.66 | 155 |