| 时间 | 值 （亿美元） | 世界排名 |
|---|---|---|
| 2015 | 14 | 107 |
| 2014 | 16 | 112 |
| 2013 | 18 | 108 |
| 2012 | 13 | 118 |
| 2011 | 11 | 120 |
| 2010 | 8 | 117 |
| 2009 | 6 | 127 |
| 2008 | 8 | 117 |
| 2007 | 8 | 114 |
| 2006 | 5 | 125 |
| 2005 | 4 | 131 |
| 2004 | 4 | 117 |
| 2003 | 4 | 112 |
| 2002 | 4 | 109 |
| 2001 | 4 | 105 |
| 2000 | 3 | 109 |
| 1999 | 3 | 105 |
| 1998 | 3 | 105 |
| 1997 | 3 | 105 |
| 1991 | 4 | 79 |
| 1990 | 4 | 74 |
| 1989 | 4 | 71 |
| 1988 | 3 | 80 |
| 1987 | 2 | 82 |
| 1986 | 2 | 83 |