I have a source School Absences Table for a pivot table. Each row of the table represents one student being absent for a date. So there are many rows for each day. The row contains a unique student id, the school year the student is in and other absence data e.g. term number, week number and day of the week etc. In the pivot table I can count the student id and get the total number of absences in one day but I needs to show the average number of absences per day over various time filters. It means getting the total number of absences for EACH day and averaging this number over the number of days in the particular time filter. How is this achieved?