I have a table that has, for several items, the cost and the current value of the item:

Item. Cost. Value. Multiple (formula = value/cost)

A. 10. 20. 2

B. 5. 15. 3

C. 1. 1. 1

D. 10. 5. 0.5

For this table I need a summary. For Cost & Value, i can use the Sum function and it works just fine. For the multiple, none of the preset aggregators work, as I would need a weighted-average aggregator. I would need to calculate the sum of value for all items and divide by the sum of cost for all values. averaging the ratios would generate incorrect results.

How should I do this?