Formula to find correct input and output

[truxor]

Morning,

I have a range of cells that show the inputs and outputs by steps.


What I want the formula to do is grab the first input given and then grab the last output from the range.


The problem I have is that the process of the output may vary depending on which process it went through, that's where I am having trouble automating it.


An example:

	Input	Output A	Output B
Step A	100	40	0
Step B	40	35	0
Step C	30	0	30

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I don't want to put a total at the bottom for all since the output, Step C, was the actual
amount in the process. What I want is Step C Output (30) and Step A (100)
divided into each other - 30%.


How can I logically make the formula work? I have tried IFS, but getting stuck.


Also not all processes will finish with Step C, it may finish with Step A or B. I want it
to logically find the correct Input/Output.

	Input	Output A	Output B
Step A	100	40	0
Step B	40	35	0

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