1 Reply Latest reply on Feb 2, 2012 9:09 AM by susanacrespo

# This should be simple! How do you use two calculated fields to calculate a rate?

I am working for a tall, normalized table where all my elements are in one column, and the value in another.  I want to select the sum value from one element (tonnes of agricultural production) and divide it by the sum value of a second element (hectares of harvested area) to calculate the rate of yield (tonnes per hectare)

The details:

Create = # Area Harvested:

IF [element_txt] = "Area Harvested" THEN[val] ELSE NULL END

Create = # Production Quantity:

IF [element_txt] = "Production Quantity" THEN [val] ELSE NULL

Both these calculations work.  However, if I want to create the = # Yield calculation by dividing one by the other, it comes out NULL.  Here is what I am using for the third calculated field:

[Production Quantity]/[Area Harvested]

Any ideas?

• ###### 1. Re: This should be simple! How do you use two calculated fields to calculate a rate?

I think I got it!  I was missing SUM.

This is what works:

SUM([Production Quantity])/SUM([Area Harvested])