Overlapping area represents the amount of risk that can be diversified away by holding Target Corp. and Aarons Inc in the same portfolio assuming nothing else is changed. The correlation between historical prices or returns on Aarons and Target is a relative statistical measure of the degree to which these equity instruments tend to move together. The correlation coefficient measures the extent to which returns on Target Corporation are associated (or correlated) with Aarons. Values of the correlation coefficient range from -1 to +1, where. The correlation of zero (0) is possible when the price movement of Aarons has no effect on the direction of Target i.e. Target and Aarons go up and down completely randomly.