Accumulative values from a count

ahorne27,

You may also refer to the following DAX that creates a measure.

Measure =
VAR n =
    MAX ( Table1[Item Name] )
VAR t =
    MAX ( Table1[Timestamp] )
RETURN
    CALCULATE (
        SUM ( Table1[Cost Per Item x Number Sold] ),
        FILTER (
            ALLSELECTED ( Table1 ),
            Table1[Item Name] = n
                && Table1[Timestamp] <= t
        )
    )