O/Variants per time

Number of inscriptions containing variants of O per time span:

-750+	–	–	–	–	–	–	–	–
-650+	3	–	–	–	–	–	–	1
-550+	6	–	1	–	–	–	–	–
-450+	9	2	6	1	–	1	–	1
-350+	11	2	–	1	–	–	–	2
-250+	1	4	1	1	–	1	–	1
-150+	5	27	29	3	1	11	–	15
-50+	2	14	9	–	1	6	1	3
50+	–	1	–	–	–	–	–	2
150+	1	–	–	–	–	–	–	–