| 时间 | 值 （亿美元） | 世界排名 |
|---|---|---|
| 2015 | 1 | 195 |
| 2014 | 2 | 195 |
| 2013 | 2 | 196 |
| 2012 | 1 | 197 |
| 2011 | 1 | 195 |
| 2010 | 1 | 192 |
| 2009 | 1 | 192 |
| 2008 | 1 | 192 |
| 2007 | 1 | 193 |
| 2006 | 1 | 193 |
| 2005 | 0 | 192 |
| 2004 | 0 | 194 |
| 2003 | 0 | 192 |
| 2002 | 0 | 191 |
| 2001 | 0 | 191 |
| 2000 | 0 | 191 |
| 1999 | 0 | 191 |
| 1998 | 0 | 190 |
| 1997 | 0 | 189 |
| 1996 | 0 | 189 |
| 1995 | 0 | 189 |
| 1994 | 0 | 188 |
| 1993 | 0 | 171 |
| 1992 | 0 | 172 |
| 1991 | 0 | 164 |
| 1990 | 0 | 165 |
| 1989 | 0 | 164 |
| 1988 | 0 | 164 |
| 1987 | 0 | 164 |
| 1986 | 0 | 163 |