Keyword Analysis & Research: why can i not merge cells in excel table

Keyword Analysis

Keyword	CPC	PCC	Volume	Score	Length of keyword
why can i not merge cells in excel table	1.47	0.1	9696	80	40
why	1.67	0.6	2896	53	3
can	0.75	0.5	3553	100	3
i	0.16	1	3283	5	1
not	1.3	0.1	5608	56	3
merge	0.19	0.9	8233	95	5
cells	0.24	0.5	4961	56	5
in	1.14	0.4	4942	98	2
excel	0.54	0.8	3879	33	5
table	0.17	0.1	4802	36	5

Keyword	CPC	PCC	Volume	Score
why can i not merge cells in excel table	1.79	0.4	6345	28