| 时间 | 值 （亿美元） | 世界排名 |
|---|---|---|
| 2015 | 92.8 | 31 |
| 2014 | 19.2 | 71 |
| 2013 | -71.2 | 194 |
| 2012 | -69 | 196 |
| 2011 | -30.2 | 192 |
| 2010 | -32.3 | 193 |
| 2009 | 22.1 | 62 |
| 2008 | 16.8 | 85 |
| 2007 | -8.9 | 195 |
| 2006 | -.4 | 189 |
| 2005 | -13 | 193 |
| 2004 | 22 | 45 |
| 2003 | 35.8 | 34 |
| 2002 | 17.4 | 44 |
| 2001 | 21.5 | 39 |
| 2000 | 8.8 | 52 |
| 1999 | 24.7 | 35 |
| 1998 | 11.1 | 46 |
| 1997 | 4.1 | 66 |
| 1996 | 1.8 | 74 |
| 1995 | 4.7 | 47 |
| 1994 | 1.7 | 64 |
| 1993 | 3 | 55 |
| 1992 | 2.9 | 43 |
| 1991 | 6.6 | 32 |
| 1990 | -3.3 | 151 |
| 1989 | 2 | 40 |
| 1988 | 1.3 | 44 |
| 1987 | 1.2 | 37 |
| 1986 | 2.3 | 29 |