| 时间 | 值 （亿美元） | 世界排名 |
|---|---|---|
| 2016 | 2 | 132 |
| 2015 | 2 | 158 |
| 2014 | 2 | 161 |
| 2013 | 2 | 165 |
| 2012 | 2 | 166 |
| 2011 | 2 | 166 |
| 2010 | 2 | 169 |
| 2009 | 1 | 168 |
| 2008 | 2 | 166 |
| 2007 | 2 | 167 |
| 2006 | 1 | 170 |
| 2005 | 1 | 168 |
| 2004 | 1 | 167 |
| 2003 | 1 | 168 |
| 2002 | 1 | 169 |
| 2001 | 1 | 169 |
| 2000 | 1 | 169 |
| 1999 | 1 | 166 |
| 1998 | 1 | 166 |
| 1997 | 1 | 162 |
| 1996 | 1 | 160 |
| 1995 | 1 | 161 |
| 1994 | 1 | 144 |