| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 23.91 | 176 |
| 2015 | 24.9 | 177 |
| 2014 | 26.49 | 179 |
| 2013 | 27.47 | 182 |
| 2012 | 24.44 | 177 |
| 2011 | 17.86 | 166 |
| 2010 | 12.71 | 146 |
| 2009 | 9.62 | 128 |
| 2008 | 7.76 | 115 |
| 2007 | 8.4 | 116 |
| 2006 | 9.01 | 121 |
| 2005 | 9.99 | 125 |
| 2004 | 10.31 | 127 |
| 2003 | 9.41 | 112 |
| 2002 | 9.98 | 114 |
| 2001 | 10.46 | 124 |
| 2000 | 11.25 | 128 |
| 1999 | 11.85 | 131 |
| 1998 | 10.84 | 122 |
| 1997 | 9.58 | 109 |
| 1996 | 9.65 | 111 |
| 1995 | 9.06 | 111 |
| 1994 | 8.86 | 107 |
| 1993 | 8.61 | 104 |
| 1992 | 7.84 | 97 |
| 1991 | 7.66 | 100 |