Hi, I would like to reduce the text list (in this case room names) and at the same time sum the corresponding index values in the number list (in this case areas). As per the graph extract. Any ideas on how to do this using either nodes or would it require code? cheers Spencer [image]

Thanks very much Jacob :slight_smile: For others, nodes are as per extract. [image]

Sum numbers in one list based on duplicate text items in another list

jacob.small December 27, 2018, 5:20am 2

List.GroupByKey
Math.Sum (longest lacing).

Apartment Calculation

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