title: Filemaker - Summing a field based on another field
body: <p>In Filemaker Pro 12, I am trying to write a formula for a calculation field that will sum a field in a related table based on another field in that same related table.  The normal Filemaker sum equation would look like this:</p>
  
  <p>Sum (Assets::Asset Quantity)</p>
  
  <p>However, I need to specify that only quantities that are related to a field named Asset Type with a value of "Building" will be used to filter the values in Asset Quantity that will be used in the sum.</p>