| 时间 | 值 （亿美元） | 世界排名 |
|---|---|---|
| 2015 | 109.6 | 30 |
| 2014 | 106.2 | 30 |
| 2013 | 113 | 27 |
| 2012 | 89 | 34 |
| 2011 | 151.2 | 27 |
| 2010 | 108.9 | 30 |
| 2009 | 1.1 | 141 |
| 2008 | 75.7 | 45 |
| 2007 | 90.7 | 40 |
| 2006 | 76.9 | 38 |
| 2005 | 39.2 | 48 |
| 2004 | 43.8 | 34 |
| 2003 | 32.2 | 36 |
| 2002 | 31.9 | 32 |
| 2001 | 5.5 | 64 |
| 2000 | 37.9 | 32 |
| 1999 | 39 | 29 |
| 1998 | 21.6 | 38 |
| 1997 | 51.4 | 19 |
| 1996 | 50.8 | 16 |
| 1995 | 41.8 | 18 |
| 1994 | 43.4 | 14 |
| 1993 | 50.1 | 7 |
| 1992 | 51.8 | 8 |
| 1991 | 40 | 12 |
| 1990 | 23.3 | 16 |
| 1989 | 16.7 | 18 |
| 1988 | 7.2 | 24 |
| 1987 | 4.2 | 24 |
| 1986 | 4.9 | 20 |