| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 87.64 | 2 |
| 2015 | 87.94 | 2 |
| 2014 | 88.24 | 2 |
| 2013 | 88.53 | 2 |
| 2012 | 88.81 | 2 |
| 2011 | 89.09 | 2 |
| 2010 | 89.36 | 2 |
| 2009 | 89.62 | 2 |
| 2008 | 89.88 | 2 |
| 2007 | 90.14 | 2 |
| 2006 | 90.38 | 1 |
| 2005 | 90.63 | 1 |
| 2004 | 90.86 | 1 |
| 2003 | 91.09 | 1 |
| 2002 | 91.32 | 1 |
| 2001 | 91.54 | 1 |
| 2000 | 91.75 | 1 |
| 1999 | 91.96 | 1 |
| 1998 | 92.17 | 1 |
| 1997 | 92.38 | 1 |
| 1996 | 92.59 | 1 |
| 1995 | 92.79 | 1 |
| 1994 | 92.99 | 1 |
| 1993 | 93.18 | 1 |
| 1992 | 93.36 | 2 |
| 1991 | 93.55 | 2 |
| 1990 | 93.73 | 2 |
| 1989 | 93.95 | 2 |
| 1988 | 94.17 | 2 |
| 1987 | 94.38 | 2 |
| 1986 | 94.58 | 2 |