Year Total 1984 28 1985 33 1986 33 1987 37 1988 47 1989 46 1990 59 1991 74 1992 96 1993 104 1994 80 1995 20840 1996 38500 1997 49760 1998 67610 1999 80420 2000 115900 2001 150400 2002 177300