| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 59.16 | 59 |
| 2015 | 61.72 | 62 |
| 2014 | 54.18 | 75 |
| 2013 | 52.62 | 74 |
| 2012 | 48.12 | 76 |
| 2011 | 47.72 | 79 |
| 2010 | 51.38 | 76 |
| 2009 | 49.21 | 83 |
| 2008 | 39.43 | 91 |
| 2007 | 42.82 | 88 |
| 2006 | 37.62 | 98 |
| 2005 | 33.42 | 103 |
| 2004 | 31.12 | 107 |
| 2003 | 30 | 110 |
| 2002 | 26.43 | 116 |
| 2001 | 23.91 | 116 |
| 2000 | 21.47 | 118 |
| 1999 | 20.59 | 115 |
| 1998 | 24.1 | 105 |
| 1997 | 19.65 | 124 |
| 1996 | 17.8 | 125 |
| 1995 | 19.31 | 121 |
| 1994 | 21.24 | 115 |
| 1993 | 23.9 | 104 |