Find-Insert Column-Total Macro

[djfreex]

I have multiple data sets that looks like below in exact same format. I am trying to create a macro that subtotals in between the datasets based a particular column location. So, first subtotal column is always 12 cells to the right of the column that contains "Prod1". So, essentially macro would insert columns shaded in yellow and add up the same label columns under subtotal to that point. Note the raw data formatting includes merged cells.

Excel Workbook
	A	B	C	D	E	F	G	H	I	J	K	L	M	N	O	P	Q	R	S	T	U	V	W	X	Y	Z	AA	AB	AC	AD	AE	AF	AG
11	*	2011				*	*	*	*	*	*	*	*	*	*	*	*	*	*	*	*	*	*	*	*	*	*	*	*	*	*	*	*
12	*	Prod1				Prod2				Prod3				SubTotal				Prod4				Prod5				Prod6				SubTotal
13	*	A	B	%	C	A	B	%	C	A	B	%	C	A	B	%	C	A	B	%	C	A	B	%	C	A	B	%	C	A	B	%	C
14	Name	*	*	*	*	*	*	*	*	*	*	*	*	*	*	*	*	*	*	*	*	*	*	*	*	*	*	*	*	*	*	*	*
15	Rep1	12	5	42%	0	12	5	42%	0	12	5	42%	0	36	15	42%	0	12	5	42%	0	12	5	42%	0	12	5	42%	0	36	15	42%	0
16	Rep2	27	0	0%	0	27	0	0%	0	27	0	0%	0	81	0	0%	0	27	0	0%	0	27	0	0%	0	27	0	0%	0	81	0	0%	0
17	Rep3	9	0	0%	0	9	0	0%	0	9	0	0%	0	27	0	0%	0	9	0	0%	0	9	0	0%	0	9	0	0%	0	27	0	0%	0
18	Rep4	14	0	0%	0	14	0	0%	0	14	0	0%	0	42	0	0%	0	14	0	0%	0	14	0	0%	0	14	0	0%	0	42	0	0%	0
19	Rep5	35	0	0%	0	35	0	0%	0	35	0	0%	0	105	0	0%	0	35	0	0%	0	35	0	0%	0	35	0	0%	0	105	0	0%	0
Sheet1

Any help in the right direction would be appreciated. Thanks in advance.

Not even sure if this is the right way to think about this problem.