| 时间 | 值 （亿美元） | 世界排名 |
|---|---|---|
| 2016 | 17.56 | 159 |
| 2015 | 15.84 | 168 |
| 2014 | 17.03 | 171 |
| 2013 | 15.19 | 176 |
| 2012 | 21.84 | 171 |
| 2011 | 22.13 | 175 |
| 2010 | 19.86 | 175 |
| 2009 | 19.82 | 172 |
| 2008 | 19.85 | 171 |
| 2007 | 16.98 | 174 |
| 2006 | 14.61 | 175 |
| 2005 | 13.5 | 172 |
| 2004 | 12.7 | 172 |
| 2003 | 11.4 | 170 |
| 2002 | 9.91 | 169 |
| 2001 | 9.32 | 166 |
| 2000 | 9.15 | 165 |
| 1999 | 9.99 | 163 |
| 1998 | 9.67 | 163 |
| 1997 | 9.38 | 162 |
| 1996 | 10.08 | 162 |
| 1995 | 11.15 | 160 |
| 1994 | 8.51 | 155 |
| 1993 | 12.79 | 144 |
| 1992 | 14.12 | 142 |
| 1991 | 13.77 | 144 |
| 1990 | 14.41 | 141 |
| 1989 | 12.34 | 127 |
| 1988 | 12.65 | 126 |
| 1987 | 12.01 | 122 |
| 1986 | 11.22 | 122 |