| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 64.33 | 64 |
| 2015 | 62.18 | 76 |
| 2014 | 74.12 | 63 |
| 2013 | 73.86 | 71 |
| 2012 | 74.2 | 72 |
| 2011 | 73.96 | 70 |
| 2010 | 55.45 | 108 |
| 2009 | 52.65 | 107 |
| 2008 | 81.47 | 66 |
| 2007 | 75.85 | 69 |
| 2006 | 78.1 | 63 |
| 2005 | 80.95 | 56 |
| 2004 | 68.44 | 75 |
| 2003 | 59.69 | 79 |
| 2002 | 58.38 | 87 |
| 2001 | 57.8 | 89 |
| 2000 | 79.71 | 52 |
| 1999 | 83.75 | 38 |
| 1998 | 83.25 | 38 |
| 1997 | 86.31 | 32 |
| 1996 | 84.8 | 33 |
| 1995 | 88.48 | 24 |
| 1994 | 83.57 | 27 |
| 1993 | 75.61 | 31 |
| 1992 | 89.2 | 18 |
| 1991 | 97.03 | 15 |
| 1990 | 100.42 | 17 |
| 1989 | 83.36 | 28 |
| 1988 | 77.1 | 28 |
| 1987 | 79.28 | 23 |
| 1986 | 49.33 | 69 |