| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 80.74 | 7 |
| 2015 | 80.73 | 7 |
| 2014 | 80.73 | 7 |
| 2013 | 80.72 | 7 |
| 2012 | 81.96 | 5 |
| 2011 | 85.2 | 3 |
| 2010 | 84.63 | 3 |
| 2009 | 82.27 | 5 |
| 2008 | 79.63 | 11 |
| 2007 | 80.96 | 7 |
| 2006 | 80.14 | 8 |
| 2005 | 79.49 | 9 |
| 2004 | 78.87 | 9 |
| 2003 | 80.09 | 8 |
| 2002 | 80.96 | 6 |
| 2001 | 81.6 | 6 |
| 2000 | 79.16 | 8 |
| 1999 | 78.58 | 10 |
| 1998 | 78.4 | 10 |
| 1997 | 79.3 | 9 |
| 1996 | 79.73 | 7 |
| 1995 | 79.64 | 8 |
| 1994 | 79.38 | 9 |
| 1993 | 80.32 | 7 |
| 1992 | 80.32 | 7 |
| 1991 | 79.91 | 8 |