the only thing that appears to be wrong in your formula is the use of double quotes for the string '01: Sales' instead of single quotes. So, I'd correct the formula this way:
Let me just mention as a side comment that this calculation will get a lot slower than it should be, especially when you add all other options. Qlik Sense will calculate all the possible formulas and show one of the results to you. If your data is very small, than this may not be a concern, otherwise, I'd look for other ways of reaching the same effect.
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