| 时间 | 值 （亿美元） | 世界排名 |
|---|---|---|
| 2015 | 117.6 | 27 |
| 2014 | 50.7 | 43 |
| 2013 | 98.2 | 31 |
| 2012 | 153.2 | 24 |
| 2011 | 108.4 | 31 |
| 2010 | 113.3 | 29 |
| 2009 | 40.2 | 48 |
| 2008 | 97.3 | 37 |
| 2007 | 64.7 | 48 |
| 2006 | 55.4 | 45 |
| 2005 | 52.7 | 41 |
| 2004 | 41.2 | 35 |
| 2003 | 16.5 | 48 |
| 2002 | 21.5 | 38 |
| 2001 | 21.7 | 38 |
| 2000 | 104.2 | 22 |
| 1999 | 239.9 | 11 |
| 1998 | 72.9 | 18 |
| 1997 | 91.6 | 12 |
| 1996 | 69.5 | 11 |
| 1995 | 56.1 | 13 |
| 1994 | 36.3 | 16 |
| 1993 | 27.9 | 14 |
| 1992 | 44.3 | 10 |
| 1991 | 24.4 | 16 |
| 1990 | 18.4 | 19 |
| 1989 | 10.3 | 26 |
| 1988 | 11.5 | 16 |
| 1987 | -.2 | 136 |
| 1986 | 5.7 | 19 |