The VARIANCE function returns a numeric value that approximates the variance of its arguments.
The function type is numeric.
The returned value is the approximation of the variance of the argument-1 series.
The returned value is defined as the square of the standard deviation of the argument-1 series. This value is calculated as follows:
If the argument-1 series consists of only one value, or if the argument-1 series consists of all variable-occurrence data items and the total number of occurrences for all of them is one, the returned value is zero.