| 时间 | 值 （亿美元） | 世界排名 |
|---|---|---|
| 2015 | 26 | 88 |
| 2014 | 26 | 92 |
| 2013 | 24 | 93 |
| 2012 | 23 | 93 |
| 2011 | 22 | 94 |
| 2010 | 18 | 96 |
| 2009 | 17 | 95 |
| 2008 | 16 | 98 |
| 2007 | 14 | 100 |
| 2006 | 12 | 97 |
| 2005 | 11 | 96 |
| 2004 | 9 | 91 |
| 2003 | 7 | 96 |
| 2002 | 6 | 92 |
| 2001 | 6 | 90 |
| 2000 | 6 | 89 |
| 1999 | 7 | 82 |
| 1998 | 9 | 72 |
| 1997 | 7 | 78 |
| 1996 | 9 | 72 |
| 1995 | 7 | 70 |
| 1994 | 4 | 81 |
| 1993 | 6 | 70 |
| 1992 | 3 | 82 |
| 1991 | 3 | 83 |
| 1990 | 3 | 84 |
| 1989 | 3 | 81 |
| 1988 | 3 | 79 |
| 1987 | 2 | 80 |
| 1986 | 2 | 77 |