| 时间 | 值 （亿美元） | 世界排名 |
|---|---|---|
| 2015 | 4 | 138 |
| 2014 | 4 | 146 |
| 2013 | 5 | 150 |
| 2012 | 4 | 149 |
| 2011 | 5 | 147 |
| 2010 | 4 | 145 |
| 2009 | 4 | 143 |
| 2008 | 4 | 146 |
| 2007 | 3 | 144 |
| 2006 | 3 | 142 |
| 2005 | 2 | 141 |
| 2004 | 2 | 129 |
| 2003 | 2 | 129 |
| 2002 | 1 | 133 |
| 2001 | 1 | 129 |
| 2000 | 1 | 131 |
| 1999 | 1 | 129 |
| 1998 | 1 | 124 |
| 1997 | 2 | 121 |
| 1996 | 2 | 113 |
| 1995 | 1 | 115 |
| 1994 | 1 | 117 |
| 1993 | 1 | 112 |
| 1992 | 2 | 96 |
| 1991 | 3 | 87 |
| 1990 | 2 | 91 |
| 1989 | 2 | 96 |
| 1988 | 2 | 92 |
| 1987 | 2 | 89 |
| 1986 | 2 | 87 |