| 时间 | 值 （亿美元） | 世界排名 |
|---|---|---|
| 2011 | 60.75 | 151 |
| 2010 | 53.51 | 152 |
| 2009 | 55.57 | 146 |
| 2008 | 69.19 | 140 |
| 2007 | 59.74 | 140 |
| 2006 | 46.63 | 145 |
| 2005 | 42.8 | 145 |
| 2004 | 41.1 | 141 |
| 2003 | 35.89 | 137 |
| 2002 | 29.06 | 145 |
| 2001 | 26.71 | 141 |
| 2000 | 26.48 | 141 |
| 1999 | 29.06 | 138 |
| 1998 | 29.35 | 135 |
| 1997 | 28.4 | 134 |
| 1996 | 31.38 | 131 |
| 1995 | 31.3 | 128 |
| 1994 | 27.2 | 123 |
| 1993 | 25.74 | 122 |
| 1992 | 27.37 | 122 |
| 1991 | 24.8 | 128 |
| 1990 | 24.81 | 130 |
| 1989 | 20.1 | 119 |
| 1988 | 20.01 | 119 |
| 1987 | 18.39 | 115 |
| 1986 | 15.15 | 112 |