Timeline for all types of items produced by
Sigma Enterprises, Inc. [Tokyo, Japan]

Year	Items
1974	5
1975	1
1976	1
1978	1
1980	4
1981	4
1982	3
1983	2
1984	4
1985	1
1987	1
1988	1
1989	5
1990	6
1991	5
1992	4
1993	3
1994	1
1995	6
1996	12
1997	8
1998	10
1999	4
2000	5
2002	1

98 items with a valid date were considered for this timeline (65.77% of the total)
51 items with an invalid date.

Help us in our quest to find exact dates for:

197?: 1 item.
198?: 1 item.
199?: 25 items.
19??: 16 items.
200?: 5 items.
????: 3 items.