| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 78.54 | 19 |
| 2015 | 78.58 | 19 |
| 2014 | 78.61 | 19 |
| 2013 | 78.62 | 19 |
| 2012 | 81.39 | 14 |
| 2011 | 83.23 | 10 |
| 2010 | 84.77 | 5 |
| 2009 | 86.18 | 2 |
| 2008 | 87.47 | 2 |
| 2007 | 88.62 | 1 |
| 2006 | 89.64 | 1 |
| 2005 | 89.62 | 1 |
| 2004 | 89.52 | 1 |
| 2003 | 89.36 | 1 |
| 2002 | 89.14 | 1 |
| 2001 | 88.86 | 1 |
| 2000 | 88.89 | 1 |
| 1999 | 88.92 | 1 |
| 1998 | 88.96 | 1 |
| 1997 | 89.01 | 1 |
| 1996 | 89.07 | 1 |
| 1995 | 89.14 | 1 |
| 1994 | 89.18 | 1 |
| 1993 | 89.23 | 1 |
| 1992 | 89.28 | 2 |
| 1991 | 89.32 | 2 |
| 1990 | 89.37 | 2 |