| 时间 | 值 （亿美元） | 世界排名 |
|---|---|---|
| 2015 | 74 | 64 |
| 2014 | 74 | 65 |
| 2013 | 62 | 66 |
| 2012 | 52 | 67 |
| 2011 | 50 | 66 |
| 2010 | 41 | 68 |
| 2009 | 32 | 71 |
| 2008 | 36 | 71 |
| 2007 | 29 | 74 |
| 2006 | 23 | 76 |
| 2005 | 21 | 73 |
| 2004 | 19 | 68 |
| 2003 | 16 | 66 |
| 2002 | 13 | 68 |
| 2001 | 14 | 64 |
| 2000 | 16 | 60 |
| 1999 | 13 | 62 |
| 1998 | 12 | 65 |
| 1997 | 12 | 64 |
| 1996 | 11 | 65 |
| 1995 | 12 | 57 |
| 1994 | 9 | 64 |
| 1993 | 8 | 66 |
| 1992 | 6 | 63 |
| 1991 | 6 | 62 |
| 1990 | 6 | 62 |
| 1989 | 6 | 53 |
| 1988 | 5 | 61 |
| 1987 | 4 | 63 |
| 1986 | 4 | 59 |