Code to Alter value by adding 1 to value in cell 4 rows above

I have some rather involved code that i want to add a stpe to.
I want to have the work*** to always check to see that betwen cells
(A24:A280), but not all cells between only every 4th cell.
IE. A24,A28,A32 etc.
I want a code to make sure, in the instance that i delete rows between say
A28:A31, then i want to he code to look at the last value in the range(say
A24),
and add 1 to the value and place it in cell A32.

Example:
A24 = 1
A28 = 2
A32 = 3
A36 = 4

If i delete the rows from A28:A31.
A32 needs to change from a value of "3" to a value of "2",
and A36 from 4 to 3 etc....
which is 1 more than the previous.
Hope i am explaining this clearly.
Any idea's?
Corey....


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