Timeline for all types of items produced by
Britannica Soft. [San Francisco, CA, USA]

Year	Items
1984	1
1985	1
1988	1
1989	4
1990	1

8 items with a valid date were considered for this timeline (80.00% of the total)
2 items with an invalid date.

Help us in our quest to find exact dates for:

198?: 2 items.