when did the voting age change from 21 to 18

Keyword Analysis

Keyword	CPC	PCC	Volume	Score	Length of keyword
when did the voting age change from 21 to 18	1.94	0.2	6710	80	44
when	1.28	0.9	6712	99	4
did	0.31	1	9527	61	3
the	1.58	0.4	9244	39	3
voting	0.96	0.8	591	97	6
age	1.21	0.6	3684	24	3
change	0.57	1	1906	97	6
from	1.14	0.9	3296	57	4
21	1.14	0.1	8949	94	2
to	0.76	0.8	7973	87	2
18	1.9	0.4	6883	53	2

Keyword	CPC	PCC	Volume	Score
when did the voting age change from 21 to 18	0.88	0.3	5146	29
year voting age change from 21 to 18	1.11	0.7	5554	31
what year did voting age change from 21 to 18	1.77	0.6	3372	48
voting age change from 21 to 18	1.6	0.7	1635	67
usa voting age 21 change to 18	0.76	1	6286	73
why did the voting age change from 21 to 18	1.87	0.8	4486	19
why was the voting age change from 21 to 18	0.17	0.1	4247	28
voting age reduced from 21 to 18	1.74	0.2	3653	16
voting age 21 to 18	0.72	0.4	8626	20
when did voting age change to 18	0.37	0.7	7532	72
voting age from 21 to 18 amendment	0.51	0.5	4323	74
changing the voting age to 18	1.66	0.9	3566	5
voting age to 21	0.41	0.3	3109	40
when was voting age changed to 18	0.79	0.1	2430	27
voting age set to 18 years	0.41	1	2737	89
who changed the voting age to 18	1.68	1	2189	30
change the voting age to 16	0.41	1	6748	49
raising the voting age to 21	0.5	0.6	9307	94
should voting age be raised to 21	1.68	0.4	4804	54
when did voting age go to 18	1	0.8	3171	70
voting age nationally established as age 18	1.13	0.5	5976	96
changing the voting age to 16	0.09	0.4	4260	7