| 时间 | 值 （亿美元） | 世界排名 |
|---|---|---|
| 2013 | 12 | 120 |
| 2012 | 11 | 120 |
| 2011 | 11 | 116 |
| 2010 | 11 | 110 |
| 2009 | 11 | 102 |
| 2008 | 14 | 101 |
| 2007 | 10 | 108 |
| 2006 | 6 | 116 |
| 2005 | 5 | 122 |
| 2004 | 5 | 111 |
| 2003 | 5 | 105 |
| 2002 | 6 | 97 |
| 2001 | 4 | 98 |
| 2000 | 4 | 102 |
| 1999 | 3 | 103 |
| 1998 | 3 | 103 |
| 1997 | 3 | 103 |
| 1996 | 3 | 102 |
| 1995 | 4 | 89 |
| 1994 | 3 | 91 |
| 1993 | 3 | 93 |
| 1992 | 2 | 89 |
| 1991 | 2 | 94 |
| 1990 | 2 | 97 |
| 1989 | 2 | 97 |
| 1988 | 2 | 95 |
| 1987 | 2 | 95 |
| 1986 | 2 | 91 |