| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 75.88 | 84 |
| 2015 | 75.9 | 84 |
| 2014 | 75.92 | 83 |
| 2013 | 76.01 | 83 |
| 2012 | 76.12 | 81 |
| 2011 | 76.23 | 81 |
| 2010 | 76.32 | 76 |
| 2009 | 76.44 | 73 |
| 2008 | 76.53 | 74 |
| 2007 | 76.62 | 73 |
| 2006 | 76.7 | 74 |
| 2005 | 76.79 | 74 |
| 2004 | 76.87 | 74 |
| 2003 | 76.93 | 74 |
| 2002 | 77.02 | 74 |
| 2001 | 77.1 | 76 |
| 2000 | 77.17 | 79 |
| 1999 | 77.22 | 80 |
| 1998 | 77.26 | 83 |
| 1997 | 77.28 | 81 |
| 1996 | 77.3 | 84 |
| 1995 | 77.33 | 86 |
| 1994 | 77.31 | 87 |
| 1993 | 77.3 | 89 |
| 1992 | 77.29 | 90 |
| 1991 | 77.25 | 90 |
| 1990 | 77.32 | 92 |