| 时间 | 值 （亿美元） | 世界排名 |
|---|---|---|
| 2016 | 616 | 8 |
| 2015 | 705.8 | 8 |
| 2014 | 739.9 | 7 |
| 2013 | 646.8 | 9 |
| 2012 | 562.4 | 9 |
| 2011 | 491.6 | 10 |
| 2010 | 550.8 | 9 |
| 2009 | 238.2 | 15 |
| 2008 | 122 | 30 |
| 2007 | 477.3 | 17 |
| 2006 | 369.2 | 13 |
| 2005 | 180.9 | 17 |
| 2004 | 243.9 | 10 |
| 2003 | 170.5 | 14 |
| 2002 | 61.6 | 21 |
| 2001 | 170.1 | 13 |
| 2000 | 155.2 | 16 |
| 1999 | 165.8 | 15 |
| 1998 | 73.1 | 17 |
| 1997 | 137.5 | 6 |
| 1996 | 96.8 | 7 |
| 1995 | 115.4 | 9 |
| 1994 | 85.5 | 7 |
| 1993 | 46.9 | 9 |
| 1992 | 22 | 14 |
| 1991 | 48.9 | 7 |
| 1990 | 55.7 | 9 |
| 1989 | 28.9 | 10 |
| 1988 | 36.5 | 9 |
| 1987 | 28.4 | 9 |
| 1986 | 17.1 | 12 |