| Year | Total trade | % ≥ 5 from previous year | Year | Total trade | % ≥ 5 from previous year | Year | Total trade | % ≥ 5 from previous year |
| 1987 | 3461 | - | 1988 | 3675 | 6.2 | 1989 | 3860 | 5 |
| 1990 | 3977 | - | 1991 | 4110 | - | 1992 | 4221 | - |
| 1993 | 4339 | - | 1994 | 4506 | - | 1995 | 4712 | - |
| 1996 | 4906 | - | 1997 | 5168 | 5.3 | 1998 | 5172 | - |
| 1999 | 5296 | - | 2000 | 5595 | 5.6 | 2001 | 5653 | - |
| 2002 | 5820 | - | 2003 | 6133 | 5.4 | 2004 | 6493 | 5.9 |
| 2005 | 6720 | 5.9 | 2006 | 7195 | 7.1 | 2007 | 7572 | 5.2 |