| 时间 | 值 （美元） | 世界排名 |
|---|---|---|
| 2016 | 17374 | 22 |
| 2015 | 16830 | 29 |
| 2014 | 16350 | 29 |
| 2013 | 16045 | 29 |
| 2012 | 16507 | 29 |
| 2011 | 17119 | 28 |
| 2010 | 17594 | 30 |
| 2009 | 17631 | 28 |
| 2008 | 18455 | 27 |
| 2007 | 18876 | 25 |
| 2006 | 18621 | 26 |
| 2005 | 18245 | 26 |
| 2004 | 17842 | 25 |
| 2003 | 17449 | 23 |
| 2002 | 17354 | 24 |
| 2001 | 17089 | 22 |
| 2000 | 16589 | 21 |
| 1999 | 15937 | 21 |
| 1998 | 15256 | 22 |
| 1997 | 14668 | 23 |
| 1996 | 14320 | 24 |
| 1995 | 14035 | 24 |
| 1994 | 13859 | 22 |
| 1993 | 13776 | 20 |
| 1992 | 14116 | 19 |
| 1991 | 13884 | 20 |
| 1990 | 13529 | 21 |
| 1989 | 13083 | 20 |
| 1988 | 12429 | 19 |
| 1987 | 11875 | 19 |
| 1986 | 11237 | 19 |