title: Tableau calculated column based on another column
body: <p>The following Tableau calculated field calculates properly for my entire dataset: sum([Total Risk])/sum([TotalACV])</p>
  
  <p>However, there is an additional column called AccountNumber - there are 9000 unique account numbers in my data set and multiple entries per Account Number.</p>
  
  <p>I would like to change the calculation above so it calculates based on the individual AccountNumber, not the entire data set.</p>