| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 76.45 | 41 |
| 2015 | 76.45 | 42 |
| 2014 | 76.43 | 40 |
| 2013 | 76.63 | 40 |
| 2012 | 76.82 | 36 |
| 2011 | 77.41 | 34 |
| 2010 | 77.9 | 32 |
| 2009 | 77.85 | 34 |
| 2008 | 78.2 | 33 |
| 2007 | 79.01 | 31 |
| 2006 | 79.16 | 29 |
| 2005 | 79.63 | 27 |
| 2004 | 79.73 | 26 |
| 2003 | 79.59 | 26 |
| 2002 | 79.2 | 28 |
| 2001 | 79.55 | 27 |
| 2000 | 78.97 | 35 |
| 1999 | 79.33 | 32 |
| 1998 | 79.92 | 27 |
| 1997 | 79.71 | 32 |
| 1996 | 80.42 | 28 |
| 1995 | 80.68 | 28 |
| 1994 | 81.18 | 27 |
| 1993 | 81.04 | 28 |
| 1992 | 81.46 | 27 |
| 1991 | 81.6 | 27 |