| 时间 | 值 （亿美元） | 世界排名 |
|---|---|---|
| 2016 | 84.1 | 26 |
| 2015 | 22.4 | 64 |
| 2014 | 131.1 | 25 |
| 2013 | 108 | 28 |
| 2012 | 219.8 | 21 |
| 2011 | 98.2 | 34 |
| 2010 | 84.6 | 37 |
| 2009 | 55.8 | 40 |
| 2008 | 78.2 | 44 |
| 2007 | 60.3 | 50 |
| 2006 | 132 | 29 |
| 2005 | 44.3 | 46 |
| 2004 | 25 | 43 |
| 2003 | 103.4 | 15 |
| 2002 | 6 | 69 |
| 2001 | 61.2 | 21 |
| 2000 | 72.9 | 28 |
| 1999 | 11.7 | 45 |
| 1998 | 30 | 32 |
| 1997 | 23.6 | 37 |
| 1996 | 13.5 | 39 |
| 1995 | 6.8 | 45 |
| 1994 | 12.7 | 32 |
| 1993 | 15.3 | 22 |
| 1992 | 18.7 | 18 |
| 1991 | 24.5 | 15 |
| 1990 | 26.1 | 13 |
| 1989 | 17.4 | 17 |
| 1988 | 9.2 | 22 |
| 1987 | 4.7 | 23 |
| 1986 | 2.4 | 28 |