# Aggregate functions overview

Aggregate functions process and summarize the values of multiple rows into a single computational result. You can use aggregate functions on grouped levels, or in a total column. Add all values of a column using the Sum function, or  Count the number of values for each grouping in a column. Aggregates must always refer to columns at a lower level than the desired result.

When you group the aggregated column, Sigma calculates the aggregate for each group. For example, if the worksheet is grouped by the column [Year], then the function Sum([Revenue]) computes the revenue for each year.

You can reference the results of aggregate functions from lower levels. For example, create a Sum([Amount]) column as Total, and an [Amount] / [Total] column as Percentage. This converts each Amount value into a relative percentage value.

Avg
Determines the average value of a column or group.
AvgIf
Determines the average value for a column or group where the specified conditions are `TRUE`.
Corr
Calculates the Pearson correlation coefficient (bivariate correlation) of two columns.
Count
Calculates the number of non-null and non-empty values in a column or group.
CountDistinct
Calculates the number of unique (not repeating) values in a column or group; same as Ndv.
CountDistinctIf
Calculates the number of unique (not repeating) values in a column or group where the specified conditions are `TRUE`.
CountIf
Calculates the number of values in a column or group where the specified conditions are `TRUE`.
GrandTotal
Calculates the grand total for a grouped aggregation column.
Max
Determines the maximum value for a column or group.
MaxIf
Determines the maximum value for a column or group where the specified conditions are `TRUE`.
Median
Determines the median value of a column or group; the midpoint value in a probability distribution.
Min
Determines the minimum value for a column or group.
MinIf
Determines the minimum value for a column or group where the specified conditions are `TRUE`.
Ndv
Calculates the number of unique (not repeating) values in a column or group; same as CountDistinct.
PercentileCont
Calculates the continuous kth percentile value of a column or group.
PercentileDisc
Calculates the discrete kth percentile value of a column or group.
PercentOfTotal
Calculates the percent total for an aggregate formula.
StdDev
Calculates the standard deviation of a column or group.
Subtotal
Calculates the subtotal of a column or group.
Sum
Calculates the sum of a column or group.
SumIf
Calculates the sum of a column or group where the specified conditions are `TRUE`.
SumProduct
Calculates the sum of the product of values in a series of columns.
Variance
Calculates the statistical variance of a column or group.

The following Window functions also operate on aggregates:

ListAgg
Aggregates a column's row values into a single list, for each window; returns a text column.
ListAggDistinct
Aggregates a column's distinct (non-duplicate) row values into a single list, for each window; returns a text column.