| 时间 | 值 （美元） | 世界排名 |
|---|---|---|
| 2016 | 15886 | 23 |
| 2015 | 15554 | 30 |
| 2014 | 15485 | 30 |
| 2013 | 15318 | 31 |
| 2012 | 15608 | 31 |
| 2011 | 16878 | 30 |
| 2010 | 18673 | 27 |
| 2009 | 20001 | 22 |
| 2008 | 20395 | 23 |
| 2007 | 19741 | 23 |
| 2006 | 19017 | 23 |
| 2005 | 18558 | 25 |
| 2004 | 18031 | 24 |
| 2003 | 17446 | 24 |
| 2002 | 16729 | 26 |
| 2001 | 15978 | 25 |
| 2000 | 15500 | 24 |
| 1999 | 15180 | 24 |
| 1998 | 14724 | 25 |
| 1997 | 14159 | 25 |
| 1996 | 13621 | 25 |
| 1995 | 13325 | 25 |
| 1994 | 13058 | 24 |
| 1993 | 12873 | 24 |
| 1992 | 13049 | 23 |
| 1991 | 12857 | 24 |
| 1990 | 12647 | 23 |
| 1989 | 12455 | 22 |
| 1988 | 11780 | 21 |
| 1987 | 11147 | 21 |
| 1986 | 10894 | 21 |