AVERAGE vs AVERAGEX: Standard Averages vs Row-by-Row Averages

AVERAGE returns the arithmetic mean of values in a single column. AVERAGEX iterates over a table, evaluates an expression for each row, then averages those results—essential when the value to average is computed from multiple columns.

Choosing the wrong function leads to incorrect insights: averaging pre-aggregated totals is not the same as averaging per-line calculations.

AVERAGE(<column>)

AVERAGEX(<table>, <expression>)

• AVERAGE: Mean of one numeric column in the current filter context.
• AVERAGEX: Mean of an expression evaluated row by row across <table>.

An OrderDetails table with quantity and unit price per line (discount not stored):

AVERAGE on UnitPrice ignores quantity and discount. AVERAGEX computes the net line amount per row, then averages:

Avg Unit Price =
AVERAGE( OrderDetails[UnitPrice] )

Avg Line Value =
AVERAGEX(
    OrderDetails,
    OrderDetails[Quantity]
        * OrderDetails[UnitPrice]
        * ( 1 - OrderDetails[DiscountPct] )
)