| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 0.95 | 107 |
| 2015 | 0.86 | 125 |
| 2014 | 0.88 | 124 |
| 2013 | 0.84 | 126 |
| 2012 | 0.78 | 128 |
| 2011 | 0.76 | 123 |
| 2010 | 0.81 | 124 |
| 2009 | 0.89 | 123 |
| 2008 | 0.76 | 132 |
| 2007 | 0.79 | 122 |
| 2006 | 0.79 | 124 |
| 2005 | 0.85 | 130 |
| 2004 | 0.88 | 131 |
| 2003 | 1.06 | 120 |
| 2002 | 1.09 | 116 |
| 2001 | 1.18 | 110 |
| 2000 | 1.15 | 109 |
| 1999 | 1.22 | 104 |
| 1998 | 1.14 | 109 |
| 1997 | 1.14 | 110 |
| 1996 | 1.24 | 105 |
| 1995 | 1.47 | 95 |
| 1994 | 1.46 | 101 |
| 1993 | 1.42 | 105 |
| 1992 | 1.42 | 101 |
| 1991 | 1.51 | 91 |
| 1990 | 1.45 | 94 |
| 1989 | 1.88 | 80 |
| 1988 | 2.12 | 75 |
| 1987 | 2.28 | 66 |
| 1986 | 2.31 | 63 |