| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 52.31 | 73 |
| 2015 | 49.45 | 87 |
| 2014 | 47.73 | 86 |
| 2013 | 44.29 | 95 |
| 2012 | 45.81 | 84 |
| 2011 | 44.03 | 88 |
| 2010 | 44.37 | 91 |
| 2009 | 41.86 | 95 |
| 2008 | 36.15 | 102 |
| 2007 | 38.41 | 100 |
| 2006 | 30.98 | 113 |
| 2005 | 26.21 | 120 |
| 2004 | 22.25 | 131 |
| 2003 | 20.06 | 132 |
| 2002 | 18.44 | 136 |
| 2001 | 15.26 | 143 |
| 2000 | 15.75 | 144 |
| 1999 | 11.62 | 149 |
| 1998 | 10.82 | 147 |
| 1997 | 10.45 | 148 |