| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 73.75 | 60 |
| 2015 | 73.82 | 59 |
| 2014 | 73.77 | 59 |
| 2013 | 73.95 | 58 |
| 2012 | 73.97 | 57 |
| 2011 | 74.03 | 56 |
| 2010 | 74.13 | 52 |
| 2009 | 74.41 | 49 |
| 2008 | 74.7 | 53 |
| 2007 | 75.58 | 47 |
| 2006 | 75.79 | 43 |
| 2005 | 76.18 | 41 |
| 2004 | 76.65 | 38 |
| 2003 | 77.36 | 36 |
| 2002 | 78.02 | 37 |
| 2001 | 78.63 | 34 |
| 2000 | 79.27 | 30 |
| 1999 | 79.52 | 31 |
| 1998 | 79.82 | 28 |
| 1997 | 80.2 | 29 |
| 1996 | 80.41 | 29 |
| 1995 | 80.59 | 30 |
| 1994 | 80.87 | 30 |
| 1993 | 80.9 | 29 |
| 1992 | 80.85 | 30 |
| 1991 | 80.41 | 33 |