Sum Avg Min Max
The checkboxes in this section of the screen represent:
sum - a summary of all of the numeric values in a particular column
avg - the average of all of the numeric values in a particular column
min - the minimum value of all of the numeric values in a particular column
max - the maximum value of all of the numeric values in a particular column
When checking one or more of the options, those aggregate values will be displayed at the bottom of the appropriate column in the adhoc report output.