| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 79.69 | 8 |
| 2015 | 79.66 | 8 |
| 2014 | 79.66 | 8 |
| 2013 | 79.71 | 8 |
| 2012 | 79.75 | 8 |
| 2011 | 79.78 | 10 |
| 2010 | 79.8 | 10 |
| 2009 | 79.76 | 9 |
| 2008 | 79.72 | 9 |
| 2007 | 79.96 | 9 |
| 2006 | 80.18 | 9 |
| 2005 | 80.4 | 7 |
| 2004 | 80.62 | 7 |
| 2003 | 80.83 | 6 |
| 2002 | 81.04 | 6 |
| 2001 | 81.25 | 7 |
| 2000 | 81.46 | 6 |
| 1999 | 81.63 | 6 |
| 1998 | 81.64 | 6 |
| 1997 | 81.84 | 6 |
| 1996 | 82.21 | 6 |
| 1995 | 82.75 | 6 |
| 1994 | 81.7 | 6 |
| 1993 | 80.76 | 7 |
| 1992 | 79.99 | 8 |
| 1991 | 79.45 | 8 |
| 1990 | 79.21 | 8 |