| 时间 | 值 （亿美元） | 世界排名 |
|---|---|---|
| 2016 | 176.4 | 19 |
| 2015 | 79.9 | 36 |
| 2014 | -86.3 | 195 |
| 2013 | 15.4 | 74 |
| 2012 | 42.7 | 50 |
| 2011 | 69.8 | 44 |
| 2010 | 6.3 | 101 |
| 2009 | 89.6 | 29 |
| 2008 | 414.4 | 15 |
| 2007 | 461.4 | 18 |
| 2006 | 220.5 | 19 |
| 2005 | 207.8 | 16 |
| 2004 | 168.5 | 14 |
| 2003 | 60.1 | 23 |
| 2002 | 183.8 | 11 |
| 2001 | 182.2 | 12 |
| 2000 | 228.2 | 14 |
| 1999 | 606.3 | 3 |
| 1998 | 200.2 | 9 |
| 1997 | 102.7 | 11 |
| 1996 | 54.9 | 15 |
| 1995 | 149.4 | 5 |
| 1994 | 62.7 | 11 |
| 1993 | 37 | 13 |
| 1992 | -.1 | 155 |
| 1991 | 63.5 | 5 |
| 1990 | 19.8 | 17 |
| 1989 | 18.1 | 15 |
| 1988 | 16.7 | 14 |
| 1987 | 6.4 | 20 |
| 1986 | 10.8 | 15 |