I have a table whose records are shown as portal.  One of the fields is populated with a "Yes" or "No" and that depends on whether it is complete or not.  I'd like to have a separate field that gives me the percentage of completed tasks (Number of records with a Yes / Total Number of Records * 100).    Thanks for the help.

Try

PatternCount ( List ( otherTable::completed ) ; "Yes" ) / Count ( otherTable::primaryKey) * 100 

Having said that, it may be better to define the "completed” field as number field, and use a checkbox with a value list of 1, where a check (value of 1) indicates the task(?) is completed. Then your calculation is 

Sum ( otherTable::completed? ) / Count ( otherTable::primaryKey) * 100 

Great.  Thanks for your help.  I had done something like this and was able to get it.  Now just have to figure how to get the calculation to be applied every time the finished field is set from yes to no or vice versa..... I tried doing it with ExecuteSQL as follows:

 

ExecuteSQL ("SELECT COUNT (Finished) FROM Job_History_Task where Finished='Yes'" ; "" ; "") / ExecuteSQL ("SELECT COUNT (RecordID) FROM Job_History_Task" ; "" ; "")  *  "100"