| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 84.4 | 20 |
| 2015 | 84.15 | 21 |
| 2014 | 83.87 | 22 |
| 2013 | 83.62 | 22 |
| 2012 | 83.35 | 25 |
| 2011 | 83.07 | 26 |
| 2010 | 82.78 | 27 |
| 2009 | 82.61 | 28 |
| 2008 | 82.46 | 30 |
| 2007 | 82.32 | 27 |
| 2006 | 82.22 | 30 |
| 2005 | 82.19 | 31 |
| 2004 | 82.32 | 31 |
| 2003 | 82.58 | 33 |
| 2002 | 82.86 | 31 |
| 2001 | 83.17 | 32 |
| 2000 | 83.48 | 28 |
| 1999 | 83.84 | 26 |
| 1998 | 84.18 | 25 |
| 1997 | 84.49 | 23 |
| 1996 | 84.75 | 22 |
| 1995 | 84.95 | 23 |
| 1994 | 85.08 | 24 |
| 1993 | 85.15 | 26 |
| 1992 | 85.18 | 26 |
| 1991 | 85.19 | 27 |
| 1990 | 85.2 | 26 |