Calculates the statistical variance in a moving window.
MovingVariance(number field, above, below)
number field (required) The column to be measured.
above (required) The number of rows above the current to include.
below (optional) The number of rows below the current to include. Defaults to 0.
MovingVariance([Population 2010], 5, 5)
Calculate the variance for each Population 2010 value and 5 above and below.