| 时间 | 值 （亿美元） | 世界排名 |
|---|---|---|
| 2013 | 2 | 160 |
| 2012 | 2 | 156 |
| 2011 | 2 | 159 |
| 2010 | 2 | 156 |
| 2009 | 2 | 154 |
| 2008 | 2 | 154 |
| 2007 | 2 | 153 |
| 2006 | 1 | 154 |
| 2005 | 1 | 151 |
| 2004 | 2 | 133 |
| 2003 | 1 | 133 |
| 2002 | 1 | 131 |
| 2001 | 1 | 126 |
| 2000 | 1 | 119 |
| 1999 | 1 | 118 |
| 1998 | 1 | 118 |
| 1997 | 1 | 117 |
| 1996 | 1 | 113 |
| 1995 | 1 | 110 |
| 1994 | 1 | 105 |
| 1993 | 1 | 104 |
| 1992 | 1 | 102 |
| 1991 | 1 | 97 |
| 1990 | 1 | 103 |
| 1989 | 1 | 103 |
| 1988 | 0 | 101 |
| 1987 | 0 | 100 |
| 1986 | 0 | 99 |