Formula to add dynamic number of blank rows

I am trying to add a blank cell after a certain number of rows. This number of rows will change. I currently have data in column A. Data in column B is determined by A. In C I am using the formula-

MOD(C2+(B3<>B2),2)

to return 1 or 0 depending on the change in column B. In column D I am trying to add a blank row (or a row containing some text) after the number of similar rows in column C.

For example.
A B C D
123 RED 1 123
456 RED 1 456
789 BLUE 0 BLANK CELL
234 GREEN 1 789
642 YELLOW 0 BLANK CELL
234
BLANK CELL
642
BLANK CELL

Any ideas?

123	red	1	123
348	red	1	348
325	red	0	325
453	blue	1	blank
158	green	0	453
245	yellow	1	blank
749	yellow	1	158
			blank
			245
			749
			blank