Reference > Functions reference > Aggregate functions > StDevP
 
StDevP
Purpose 
Returns the standard deviation of a population represented by a series of non-blank values in a field.
Format 
StDevP(field{;field... })
Parameters 
field - any related field, repeating field, or set of non-repeating fields; or an expression that returns a field, repeating field, or set of non-repeating fields.
Parameters in braces { } are optional.
Data type returned 
number
Originated in 
FileMaker Pro 6.0 or earlier
Description 
Field can be any of the following:
a repeating field (repeatingField).
a field in matching related records specified by (table::field), whether or not these records appear in a portal.
several non-repeating fields in a record (field1;field2;field3...).
corresponding repetitions of repeating fields in a record (repeatingField1;repeatingField2;repeatingField3), if the result is returned in a repeating field with at least the same number of repeats.
several fields in the first matching record specified by (table::field1;table::field2;...). You can include fields from different tables (table 1::field A;table 2::field B...).
Equation
Notes 
When a referenced field is a repeating field, the StDevP function returns the standard deviation of a population in the first repetition fields, then the standard deviation of a population in the second repetition fields, and so on.
Examples 
A portal displays the related values 5, 6, 7, and 8 in the field Scores. StDevP(table::Scores) returns 1.11803398....
In the following examples:
Field1 contains two repetitions with values of 1 and 2.
Field2 contains four repetitions with values of 5, 6, 7, and 8.
Field3 contains four repetitions with values of 6, 0, 4, and 4.
Field4 contains one repetition with a value of 3.
StDevP(Field4) results in an error because the population standard deviation of a single number is not defined.
StDevP(Field2) returns 1.11803398... for a non-repeating field.
StDevP(Field1;Field2;Field3) returns 2.16024689..., 2.49443825..., 1.5, 2 for repeating fields.
Related topics 
Functions reference (category list)
Functions reference (alphabetical list)
About formulas
About functions
Defining calculation fields
Using operators in formulas