| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 79.44 | 27 |
| 2015 | 79.18 | 28 |
| 2014 | 79.21 | 29 |
| 2013 | 79.13 | 29 |
| 2012 | 79.41 | 28 |
| 2011 | 78.71 | 30 |
| 2010 | 79.12 | 28 |
| 2009 | 78.32 | 31 |
| 2008 | 77.88 | 37 |
| 2007 | 77.9 | 36 |
| 2006 | 77.71 | 34 |
| 2005 | 77.21 | 37 |
| 2004 | 78.2 | 33 |
| 2003 | 78.56 | 28 |
| 2002 | 78.09 | 35 |
| 2001 | 79.15 | 31 |
| 2000 | 79.86 | 28 |
| 1999 | 79.64 | 29 |
| 1998 | 77.21 | 43 |
| 1997 | 79.6 | 34 |
| 1996 | 81.12 | 27 |
| 1995 | 80.61 | 29 |
| 1994 | 76.37 | 53 |
| 1993 | 79.13 | 34 |
| 1992 | 79.62 | 33 |
| 1991 | 79.6 | 37 |