| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 49.82 | 63 |
| 2015 | 48.51 | 56 |
| 2014 | 47.51 | 52 |
| 2013 | 46.52 | 49 |
| 2012 | 45.63 | 43 |
| 2011 | 44.93 | 36 |
| 2010 | 44.44 | 36 |
| 2009 | 44.56 | 35 |
| 2008 | 44.94 | 34 |
| 2007 | 45.66 | 38 |
| 2006 | 46.82 | 40 |
| 2005 | 48.49 | 47 |
| 2004 | 50.74 | 65 |
| 2003 | 53.54 | 77 |
| 2002 | 56.69 | 87 |
| 2001 | 59.76 | 92 |
| 2000 | 62.5 | 98 |
| 1999 | 65.18 | 100 |
| 1998 | 67.39 | 104 |
| 1997 | 69.29 | 107 |
| 1996 | 71.28 | 108 |
| 1995 | 73.68 | 108 |
| 1994 | 75.33 | 109 |
| 1993 | 77.01 | 111 |
| 1992 | 78.63 | 111 |
| 1991 | 79.88 | 115 |
| 1990 | 80.48 | 115 |
| 1989 | 82.19 | 116 |
| 1988 | 83.66 | 120 |
| 1987 | 84.9 | 121 |
| 1986 | 85.96 | 124 |