| 时间 | 值 （%） | 世界排名 |
|---|---|---|
| 2016 | 71.82 | 83 |
| 2015 | 75.93 | 96 |
| 2014 | 78.29 | 103 |
| 2013 | 75.69 | 118 |
| 2012 | 73.55 | 121 |
| 2011 | 72.17 | 125 |
| 2010 | 73.5 | 116 |
| 2009 | 78.69 | 95 |
| 2008 | 81.06 | 110 |
| 2007 | 74.09 | 124 |
| 2006 | 89.65 | 90 |
| 2005 | 115.74 | 44 |
| 2004 | 120.23 | 40 |
| 2003 | 154.23 | 13 |
| 2002 | 119.76 | 34 |
| 2001 | 126.78 | 27 |
| 2000 | 125.34 | 29 |
| 1999 | 138.31 | 15 |
| 1998 | 132.24 | 15 |
| 1997 | 106.19 | 40 |
| 1996 | 0.03 | 179 |
| 1995 | 0.02 | 178 |
| 1994 | 0.1 | 173 |
| 1993 | 0.54 | 167 |
| 1992 | 1.92 | 166 |
| 1991 | 3.79 | 164 |
| 1990 | 15.13 | 157 |
| 1989 | 44.84 | 106 |
| 1988 | 42.5 | 102 |
| 1987 | 49.35 | 85 |
| 1986 | 42.94 | 96 |