| 时间 | 值 （亿美元） | 世界排名 |
|---|---|---|
| 2016 | 29 | 72 |
| 2015 | 27 | 83 |
| 2014 | 26 | 89 |
| 2013 | 25 | 94 |
| 2012 | 25 | 90 |
| 2011 | 25 | 92 |
| 2010 | 25 | 86 |
| 2009 | 22 | 90 |
| 2008 | 21 | 92 |
| 2007 | 21 | 89 |
| 2006 | 19 | 85 |
| 2005 | 17 | 86 |
| 2004 | 16 | 78 |
| 2003 | 15 | 77 |
| 2002 | 14 | 80 |
| 2001 | 13 | 78 |
| 2000 | 14 | 76 |
| 1999 | 16 | 74 |
| 1998 | 17 | 73 |
| 1997 | 16 | 78 |
| 1996 | 14 | 77 |
| 1995 | 15 | 77 |
| 1994 | 13 | 68 |
| 1993 | 11 | 69 |
| 1992 | 10 | 70 |
| 1991 | 9 | 80 |
| 1990 | 8 | 79 |
| 1989 | 8 | 64 |
| 1988 | 7 | 68 |
| 1987 | 7 | 66 |
| 1986 | 6 | 65 |