| 时间 | 值 （美元） | 世界排名 |
|---|---|---|
| 2016 | 24631 | 12 |
| 2015 | 24582 | 13 |
| 2014 | 24846 | 12 |
| 2013 | 25096 | 10 |
| 2012 | 25278 | 9 |
| 2011 | 25267 | 9 |
| 2010 | 25027 | 11 |
| 2009 | 24844 | 10 |
| 2008 | 24766 | 12 |
| 2007 | 24636 | 13 |
| 2006 | 24458 | 12 |
| 2005 | 24068 | 12 |
| 2004 | 23721 | 11 |
| 2003 | 23326 | 11 |
| 2002 | 23041 | 10 |
| 2001 | 22982 | 10 |
| 2000 | 22775 | 8 |
| 1999 | 22146 | 8 |
| 1998 | 21676 | 8 |
| 1997 | 21086 | 7 |
| 1996 | 21013 | 7 |
| 1995 | 20452 | 8 |
| 1994 | 20310 | 8 |
| 1993 | 19980 | 8 |
| 1992 | 20124 | 7 |
| 1991 | 19663 | 7 |
| 1990 | 19282 | 7 |
| 1989 | 18640 | 8 |
| 1988 | 18076 | 9 |
| 1987 | 17676 | 9 |
| 1986 | 17270 | 9 |