| 时间 | 值 （亿美元） | 世界排名 |
|---|---|---|
| 2015 | 17 | 102 |
| 2014 | 22 | 98 |
| 2013 | 20 | 104 |
| 2012 | 18 | 106 |
| 2011 | 16 | 106 |
| 2010 | 11 | 110 |
| 2009 | 9 | 115 |
| 2008 | 10 | 119 |
| 2007 | 7 | 125 |
| 2006 | 6 | 124 |
| 2005 | 5 | 129 |
| 2004 | 4 | 131 |
| 2003 | 4 | 128 |
| 2002 | 3 | 133 |
| 2001 | 3 | 134 |
| 2000 | 2 | 135 |
| 1999 | 3 | 132 |
| 1998 | 3 | 129 |
| 1997 | 3 | 132 |
| 1996 | 4 | 127 |
| 1995 | 5 | 117 |
| 1994 | 3 | 116 |
| 1993 | 3 | 105 |
| 1992 | 6 | 91 |
| 1991 | 9 | 75 |
| 1990 | 9 | 71 |