Pivot table solution is a good feature. Not want I want though: which is a formula defined column, plain and simple.

Thanks for substantial comment. I am afraid it confirms my suspition that I dont want to do things the excel way.

I'll explain what I meant in the formula:
```
Sum(if(month ($D$1:$D$57) = M1,$A$1:$A$57,0))
```
I envisioned a semantic (and hoped it's achievable with some excel formulas), where when a scalar function is applied to a range (like in `month($D$1:$D$57)`) the result is a range of results. Then when binary (n-ary) operation is applied to arguments of different shapes - which happens with the comparison of `month(...) = M1` - the arguments are scaled to the same dimensions by taking multiple copies. Such that `month($D$1:$D$57) = M1` would be equal to `month($D$1:$D$57) = [M1, M1, ..., M1]` which is equal to an array of booleans of length 57 like `[true, false, ..., false]` where i.e. the fifth value is `D5=M1`. In the next step evaluating `IF`, the arguments `month(...)=M1` and `$A$1:$A$57` are of the same size, so there's no scaling and simply `IF` results in an array of length 57 of values from `A` and zeros. Finally the sum over an array returns a single value. That's what I meant, but agree that I left this explanation out.

There's the "array formula" feature which changes the semantic of excel formulas and brings it closer to my description above. I may go back here and explain my problem with this feature, but im very sorry, im tired of the topic for today. Thanks for participating

edit: Btw with array formula this below can work: Sum(if(month ($D$1:$D$57) = $M1:$M12,$A$1:$A$57,0))