| 时间 | 值 （亿美元） | 世界排名 |
|---|---|---|
| 2014 | 40 | 75 |
| 2013 | 40 | 74 |
| 2012 | 39 | 73 |
| 2011 | 33 | 75 |
| 2010 | 30 | 74 |
| 2009 | 22 | 80 |
| 2008 | 25 | 76 |
| 2007 | 24 | 76 |
| 2006 | 20 | 77 |
| 2005 | 15 | 78 |
| 2004 | 12 | 79 |
| 2003 | 9 | 82 |
| 2002 | 8 | 85 |
| 2001 | 8 | 82 |
| 2000 | 7 | 83 |
| 1999 | 21 | 50 |
| 1998 | 19 | 49 |
| 1997 | 17 | 51 |
| 1996 | 12 | 62 |
| 1995 | 12 | 57 |
| 1994 | 12 | 58 |
| 1993 | 10 | 58 |
| 1992 | 8 | 55 |
| 1991 | 7 | 51 |
| 1990 | 8 | 50 |
| 1989 | 6 | 55 |
| 1988 | 6 | 52 |
| 1987 | 5 | 51 |
| 1986 | 5 | 52 |