| 时间 | 值 （亿美元） | 世界排名 |
|---|---|---|
| 2016 | 20.6 | 137 |
| 2015 | 19.3 | 163 |
| 2014 | 21.2 | 165 |
| 2013 | 16.8 | 170 |
| 2012 | 24 | 166 |
| 2011 | 24.4 | 169 |
| 2010 | 22.8 | 166 |
| 2009 | 22.3 | 165 |
| 2008 | 22.3 | 164 |
| 2007 | 18.6 | 165 |
| 2006 | 15.7 | 165 |
| 2005 | 14.6 | 162 |
| 2004 | 13.4 | 163 |
| 2003 | 11.4 | 162 |
| 2002 | 10.3 | 163 |
| 2001 | 9.8 | 159 |
| 2000 | 9.6 | 156 |
| 1999 | 10.5 | 154 |
| 1998 | 10.2 | 155 |
| 1997 | 9.6 | 156 |
| 1996 | 10.5 | 154 |
| 1995 | 11.8 | 151 |
| 1994 | 8.6 | 147 |
| 1993 | 13.5 | 137 |
| 1992 | 15.5 | 132 |
| 1991 | 14.9 | 133 |
| 1990 | 15.7 | 129 |
| 1989 | 13.1 | 113 |
| 1988 | 13.6 | 109 |
| 1987 | 13.3 | 109 |
| 1986 | 12.4 | 110 |