| 时间 | 值 （亿美元） | 世界排名 |
|---|---|---|
| 2015 | 192.5 | 108 |
| 2014 | 227.2 | 108 |
| 2013 | 218.6 | 108 |
| 2012 | 212.5 | 109 |
| 2011 | 230.6 | 102 |
| 2010 | 208.7 | 101 |
| 2009 | 217.8 | 97 |
| 2008 | 253.1 | 95 |
| 2007 | 204.1 | 97 |
| 2006 | 164.7 | 96 |
| 2005 | 157.1 | 95 |
| 2004 | 145.6 | 91 |
| 2003 | 128 | 89 |
| 2002 | 97.5 | 94 |
| 2001 | 84.8 | 96 |
| 2000 | 80.8 | 95 |
| 1999 | 78 | 95 |
| 1998 | 70.4 | 98 |
| 1997 | 53.2 | 107 |
| 1996 | 44.7 | 114 |
| 1995 | 28.2 | 130 |
| 1994 | 21.5 | 126 |