| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 13.48 | 154 |
| 2015 | 16.28 | 161 |
| 2014 | 17.29 | 163 |
| 2013 | 17.25 | 163 |
| 2012 | 15.94 | 161 |
| 2011 | 13.68 | 148 |
| 2010 | 11.62 | 138 |
| 2009 | 9.2 | 117 |
| 2008 | 8.53 | 126 |
| 2007 | 9.91 | 140 |
| 2006 | 11.13 | 143 |
| 2005 | 12.6 | 149 |
| 2004 | 13.66 | 151 |
| 2003 | 13.92 | 149 |
| 2002 | 15.05 | 152 |
| 2001 | 15.8 | 160 |
| 2000 | 15.9 | 159 |
| 1999 | 13.3 | 141 |
| 1998 | 11.03 | 125 |
| 1997 | 9.9 | 115 |
| 1996 | 10 | 115 |
| 1995 | 10.45 | 125 |
| 1994 | 10.54 | 122 |
| 1993 | 9.91 | 116 |
| 1992 | 10.56 | 123 |
| 1991 | 11.14 | 131 |