Number of Samples Based on Number of Entities in Population

(Given: 90 percent confidence interval, 5 percent precision, 50 percent participation level estimate)

Table J-1: 1-542 entities | Table J-2: 543 or more entities

Number of entities (businesses, households, etc.)*	Number of samples needed	Number of entities (businesses, households, etc.)*	Number of samples needed	Number of entities (businesses, households, etc.)*	Number of samples needed
N	n	N	n	N	n
1	1	78	61	218	121
2	2	80	62	221	122
3	3	82	63	224	123
4	4	83	64	228	124
5	5	85	65	231	125
6	6	87	66	235	126
7	7	89	67	238	127
8	8	90	68	242	128
9	9	92	69	245	129
10	10	94	70	249	130
11	11	96	71	253	131
13	12	98	72	256	132
14	13	100	73	260	133
15	14	101	74	264	134
16	15	103	75	268	135
17	16	105	76	272	136
18	17	107	77	276	137
19	18	109	78	280	138
20	19	111	79	284	139
22	20	113	80	288	140
23	21	115	81	293	141
24	22	117	82	297	142
25	23	119	83	302	143
26	24	121	84	306	144
27	25	123	85	311	145
29	26	125	86	315	146
30	27	128	87	320	147
31	28	130	88	325	148
32	29	132	89	330	149
34	30	134	90	335	150
35	31	136	91	340	151
36	32	139	92	345	152
37	33	141	93	350	153
39	34	143	94	355	154
40	35	146	95	361	155
41	36	148	96	366	156
43	37	150	97	372	157
44	38	153	98	377	158
45	39	155	99	383	159
47	40	158	100	389	160
48	41	160	101	395	161
50	42	163	102	401	162
51	43	165	103	407	163
52	44	168	104	414	164
54	45	171	105	420	165
55	46	173	106	427	166
57	47	176	107	433	167
58	48	179	108	440	168
60	49	182	109	447	169
61	50	184	110	454	170
63	51	187	111	461	171
64	52	190	112	469	172
66	53	193	113	476	173
67	54	196	114	484	174
69	55	199	115	492	175
70	56	202	116	500	176
72	57	205	117	508	177
74	58	208	118	516	178
75	59	211	119	525	179
77	60	215	120	534	180

* If your N is between values given, use the smaller number of samples

Appendix J | Table of Contents

Last updated: October 26, 2007

Local Government Central http://www.ciwmb.ca.gov/LGCentral/
Larry N. Stephens: lstephen@ciwmb.ca.gov (916) 341-6241