Further explanations of the statistics based on a PostgreSQL query on the Samian Research database can be found here

Archaeological sites dated by potters

Box = avg_datemin → avg_datemax | Whiskers = uncertainty | Color = quality

Site	Findspot	n	Average potter min date	Average potter max date	Quality start date	Quality end date	Quality time interval	Uncertainty start year	Uncertainty end year	Duration uncertain time interval
Amiens	Sq. Bocquet pit 1973	41	-20	3	0.709	0.004	0.497	7	15	16
Mainz	Emmeranstraße	29	-13	12	0.649	0.307	0.538	6	15	16
Vindonissa	Depotfund	10	-6	43	0.750	0.598	0.633	2	22	22
La Graufesenque	Fosse Cirratus	75	21	49	0.774	0.886	0.753	5	6	8
Bregenz	Samian Hoard 1913	49	25	52	0.782	0.869	0.699	6	7	10
La Graufesenque	Fosse Malaval	161	34	63	0.732	0.897	0.641	11	7	13
Cap Drammont	wreck 6	2	40	75	0.702	0.910	0.637	14	7	16
Narbonne	les ports (La Nautique)	82	40	70	0.819	0.887	0.679	8	8	12
Cirencester	fort ditch	22	41	68	0.820	0.887	0.651	8	8	12
Colchester	Pottery Shop I	24	44	74	0.826	0.874	0.647	8	10	13
Colchester	Pottery Shop II	28	47	76	0.833	0.894	0.664	9	9	12
Oberwinterthur	Keramiklager	100	48	74	0.809	0.871	0.575	10	10	14
Berlingen	tumulus	8	51	78	0.789	0.872	0.548	12	11	16
Cap de Creus	Cala Culip IV	170	52	87	0.809	0.938	0.703	11	6	12
Reims	rue de l'Equerre	16	56	84	0.828	0.902	0.622	10	9	14
Burghöfe	Geschirrdepot	7	57	84	0.834	0.888	0.582	10	10	14
Pompeii	Hoard	19	62	87	0.946	0.943	0.786	3	5	6
Inchtuthil	Gutter	3	63	97	0.955	0.887	0.700	3	12	12
Nijmegen	Barbarossastraat	7	65	85	1.000	1.000	1.000	0	0	0
Pecio del Guadiaro	Shipwreck	32	66	94	0.827	0.881	0.537	13	12	17
Köln	Hafen	26	69	90	0.968	0.979	0.871	2	2	3
Chesterholm-Vindolanda	Per.1 Ditch	9	73	102	0.914	0.937	0.722	7	7	9
Bregenz	cellar	43	81	110	0.732	0.766	0.258	25	29	39
London	Second Fire	21	102	130	0.964	0.945	0.743	4	7	8
Saalburg	Erdkastell	7	104	144	0.841	0.913	0.573	18	13	22
Castleford	Pottery Shop	70	130	160	0.941	0.949	0.676	8	8	12
Helsoven	tumulus	5	130	160	0.907	0.933	0.568	13	11	17
Bregenz	shop	6	130	155	0.919	0.924	0.518	11	12	16
Verulamium	Second Fire	6	131	161	0.915	0.941	0.604	12	10	15
Alcester	Pit	10	139	177	0.971	0.976	0.858	4	4	6
Rougham	tumulus	4	143	175	0.941	0.960	0.709	9	7	11
Budapest	Aquincum, Hoard	4	144	173	0.931	0.951	0.626	10	9	13
Eschenz	shop	31	153	191	0.937	0.895	0.539	10	21	23
Wroxeter	gutter	15	158	191	0.947	0.946	0.660	9	11	14
London	New Fresh Wharf: quay	159	161	197	0.867	0.880	0.393	23	25	34
Langenhain	store	13	195	242	0.909	0.986	0.669	19	3	19