| 时间 | 值 （亿美元） | 世界排名 |
|---|---|---|
| 2012 | 1055.3 | 28 |
| 2011 | 1504.5 | 26 |
| 2010 | 1446 | 25 |
| 2009 | 1483.2 | 24 |
| 2008 | 2128.6 | 25 |
| 2007 | 2421.7 | 26 |
| 2006 | 1766.6 | 25 |
| 2005 | 1520.5 | 24 |
| 2004 | 974.5 | 24 |
| 2003 | 669.9 | 25 |
| 2002 | 515.8 | 22 |
| 2001 | 705.8 | 19 |
| 2000 | 915.6 | 21 |
| 1999 | 622.8 | 23 |
| 1998 | 705.2 | 18 |
| 1997 | 468.8 | 22 |
| 1996 | 346.7 | 24 |
| 1995 | 259.4 | 22 |
| 1994 | 274.2 | 21 |
| 1993 | 209.9 | 24 |
| 1992 | 158.1 | 21 |
| 1991 | 92.9 | 22 |
| 1990 | 111.1 | 20 |
| 1989 | 144.6 | 16 |
| 1988 | 51.1 | 19 |