| 时间 |
值 （亿美元） |
世界排名 |
| 2016 |
1 |
131 |
| 2015 |
1 |
158 |
| 2014 |
1 |
160 |
| 2013 |
1 |
163 |
| 2012 |
1 |
164 |
| 2011 |
1 |
163 |
| 2010 |
1 |
162 |
| 2009 |
1 |
162 |
| 2008 |
1 |
160 |
| 2007 |
1 |
162 |
| 2006 |
1 |
162 |
| 2005 |
1 |
161 |
| 2004 |
1 |
163 |
| 2003 |
1 |
165 |
| 2002 |
1 |
163 |
| 2001 |
1 |
164 |
| 2000 |
1 |
165 |
| 1999 |
1 |
159 |
| 1998 |
1 |
160 |
| 1997 |
1 |
160 |
| 1996 |
0 |
158 |
| 1995 |
0 |
159 |