| 时间 | 值 （亿美元） | 世界排名 |
|---|---|---|
| 2016 | 789.3 | 7 |
| 2015 | 746.9 | 7 |
| 2014 | 968.9 | 5 |
| 2013 | 691.8 | 6 |
| 2012 | 866.1 | 5 |
| 2011 | 1011.6 | 5 |
| 2010 | 884.5 | 5 |
| 2009 | 314.8 | 12 |
| 2008 | 507.2 | 12 |
| 2007 | 445.8 | 19 |
| 2006 | 193.8 | 24 |
| 2005 | 154.6 | 19 |
| 2004 | 181.8 | 13 |
| 2003 | 101.2 | 16 |
| 2002 | 165.9 | 14 |
| 2001 | 232.3 | 11 |
| 2000 | 329.9 | 11 |
| 1999 | 285.8 | 8 |
| 1998 | 319.1 | 5 |
| 1997 | 196.5 | 5 |
| 1996 | 112 | 6 |
| 1995 | 48.6 | 14 |
| 1994 | 30.7 | 18 |
| 1993 | 12.9 | 25 |
| 1992 | 20.6 | 16 |
| 1991 | 11 | 28 |
| 1990 | 9.9 | 26 |
| 1989 | 11.3 | 23 |
| 1988 | 28 | 11 |
| 1987 | 11.7 | 15 |
| 1986 | 3.5 | 24 |