| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 76.24 | 81 |
| 2015 | 76.43 | 79 |
| 2014 | 76.65 | 75 |
| 2013 | 76.82 | 74 |
| 2012 | 77.58 | 65 |
| 2011 | 77.3 | 69 |
| 2010 | 77.49 | 66 |
| 2009 | 77.65 | 65 |
| 2008 | 77.28 | 68 |
| 2007 | 77.67 | 64 |
| 2006 | 77.42 | 67 |
| 2005 | 76.71 | 75 |
| 2004 | 76.13 | 79 |
| 2003 | 76.63 | 76 |
| 2002 | 77.28 | 73 |
| 2001 | 77.97 | 72 |
| 2000 | 78.37 | 71 |
| 1999 | 78.62 | 73 |
| 1998 | 78.44 | 76 |
| 1997 | 79.13 | 75 |
| 1996 | 80.02 | 69 |
| 1995 | 78.87 | 78 |
| 1994 | 80.5 | 65 |
| 1993 | 80.33 | 66 |
| 1992 | 80.68 | 63 |
| 1991 | 80.68 | 64 |
| 1990 | 79.25 | 80 |