| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 77.81 | 11 |
| 2015 | 77.72 | 11 |
| 2014 | 77.65 | 10 |
| 2013 | 77.68 | 10 |
| 2012 | 77.75 | 10 |
| 2011 | 77.83 | 11 |
| 2010 | 77.94 | 12 |
| 2009 | 78.11 | 11 |
| 2008 | 78.27 | 11 |
| 2007 | 78.46 | 11 |
| 2006 | 78.65 | 10 |
| 2005 | 78.87 | 9 |
| 2004 | 79.06 | 9 |
| 2003 | 79.22 | 9 |
| 2002 | 79.36 | 9 |
| 2001 | 79.5 | 9 |
| 2000 | 79.61 | 8 |
| 1999 | 79.71 | 8 |
| 1998 | 79.83 | 8 |
| 1997 | 79.85 | 8 |
| 1996 | 79.93 | 8 |
| 1995 | 80.01 | 8 |
| 1994 | 80.02 | 8 |
| 1993 | 80.04 | 8 |
| 1992 | 80.01 | 7 |
| 1991 | 79.97 | 7 |
| 1990 | 79.93 | 7 |