Public MustOverride Sub Aggregate( _
   ByVal dataValue As Object, _
   ByVal summaryResult As SummaryResult, _
   ByVal record As Record _
) 

public abstract void Aggregate( 
   object dataValue,
   SummaryResult summaryResult,
   Record record
)

Parameters

dataValue

Data value to process into calculation

summaryResult

SummaryResult object for which the summary is being calculated.

record

The record associated with the data value.

This method is called for each data value that is to be aggregated into the calculation.

Note thatsummaryResult and record parameters are for extra context only and typically it's not necessary to look at them or take them into account for calculation purposes. The dataValue should suffice for most purposes.

Reference