why did the voting age change from 21 to 18

Keyword Analysis

Keyword	CPC	PCC	Volume	Score	Length of keyword
why did the voting age change from 21 to 18	1.76	1	3947	1	43
why	0.61	0.2	3539	37	3
did	1.76	0.8	9222	76	3
the	1.24	0.2	1020	7	3
voting	1.32	0.1	8580	84	6
age	0.04	0.7	656	25	3
change	0.21	0.4	9619	99	6
from	1.54	0.8	6422	31	4
21	1.82	0.5	8440	58	2
to	1.61	0.3	1806	25	2
18	0.65	0.4	4406	55	2

Keyword	CPC	PCC	Volume	Score
why did the voting age change from 21 to 18	1.48	0.9	5318	42
when did the voting age change from 21 to 18	1.01	1	4001	30
why was the voting age change from 21 to 18	0.07	1	9977	35
voting age change from 21 to 18	0.17	0.6	9887	94
when did voting age change to 18	1.28	0.9	5120	67
voting age reduced from 21 to 18	1.82	0.7	9365	98
voting age change to 21	1.94	0.9	3308	81
who changed the voting age to 18	0.97	0.1	6459	56
voting age changed to 18	1.56	0.8	5388	94
when did the voting age change	1.29	0.7	273	91
why is the voting age at 18	0.57	0.6	576	39
what year did the voting age change	0.49	1	8575	58
changing the voting age to 18	0.66	0.8	9806	85
was the voting age ever 21	1.01	0.9	1648	15
why should the voting age be changed	1.89	0.7	1046	13
voting age lowered to 18	1.25	0.7	4130	68