Year Total 1990 300000 1991 370000 1992 500000 1993 680000 1994 850000 1995 1100000 1996 1200000 1997 1500000 1998 1900000 1999 2400000 2000 2670000 2001 3300000 2002 4079000 2003 5480000 2004 4520000 2005 5346000 2006 6456000