| 时间 | 值 （亿美元） | 世界排名 |
|---|---|---|
| 2012 | 119.7 | 47 |
| 2011 | 101.4 | 49 |
| 2010 | 129.2 | 50 |
| 2009 | 235.3 | 43 |
| 2008 | 543.6 | 38 |
| 2007 | 1004.5 | 38 |
| 2006 | 1265.6 | 27 |
| 2005 | 1410 | 26 |
| 2004 | 738.7 | 28 |
| 2003 | 666 | 26 |
| 2002 | 260.3 | 32 |
| 2001 | 124.5 | 34 |
| 2000 | 329.7 | 29 |
| 1999 | 210.6 | 31 |
| 1998 | 90.4 | 41 |
| 1997 | 114.8 | 38 |
| 1996 | 60.5 | 40 |
| 1995 | 32.1 | 42 |
| 1994 | 32 | 40 |
| 1993 | 18.4 | 41 |
| 1992 | 9.8 | 41 |
| 1991 | 6.2 | 40 |
| 1990 | 2.3 | 37 |
| 1989 | 1.9 | 37 |
| 1988 | 1.8 | 36 |