| 时间 | 值 （亿美元） | 世界排名 |
|---|---|---|
| 2015 | 6 | 128 |
| 2014 | 5 | 141 |
| 2013 | 5 | 145 |
| 2012 | 3 | 156 |
| 2011 | 3 | 154 |
| 2010 | 3 | 152 |
| 2009 | 1 | 159 |
| 2008 | 1 | 165 |
| 2007 | 0 | 174 |
| 2006 | 0 | 172 |
| 2005 | 0 | 170 |
| 2004 | 0 | 158 |
| 2003 | 0 | 156 |
| 2002 | 0 | 154 |
| 2001 | 0 | 147 |
| 2000 | 0 | 147 |
| 1999 | 1 | 134 |
| 1998 | 2 | 119 |
| 1997 | 2 | 112 |
| 1996 | 1 | 124 |
| 1995 | 1 | 118 |
| 1994 | 1 | 109 |
| 1993 | 1 | 121 |
| 1992 | 1 | 113 |
| 1991 | 0 | 118 |
| 1990 | 0 | 125 |
| 1989 | 0 | 124 |
| 1988 | 0 | 120 |
| 1987 | 0 | 112 |
| 1986 | 0 | 111 |