Auto adjust a formula in excel

[sskgraham]

I have an excel file with 3 columns. They are date, units sold and the sum of units sold.
Column E has Sale method. Cell "E2" would specify the sale method.
There are 2 kinds of Sale methods. One is "Regular" and the other is "Deferred".

Regular Sale method is as follows.
The units are always sold in either June or December. All the months from Jan to Jun are sold in June and from July to December are sold in December. This keeps repeating for every year.

I was able to create a sheet for the Regular sale in the "Regular" worksheet.

Deferred sale is as follows.
There is a 6 months lag in the sale period. The units from Jan to June are sold in December and from July to December are sold in Jan. My required output is shown in "Deferred" Sheet.

I would like to create a formula in a single sheet and a single column ( Column C), which can handle both Deferred or Regular and can give me the output. The user has to refer to cell "E2" in the formula in column C.
How can I do this? Please suggest. The file is attached.

 

[SkipVought]

sskgraham,

How about a response to suggested solutions? In you four previous threads, your only response was to provide more information. You have posted NOTHING in reply to solutions that have been offered for you benefit. Other members browse these threads looking for information and solutions, and your threads provide nothing of help for others.

BTW, there is no file attached.

Skip,
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