Notes: A zero value for the MEI has been associated with the Midwest economy expanding at its historical trend (average) rate of growth; positive values with above-average growth (in standard deviation units); and negative values with below-average growth. A zero value for the relative MEI has been associated with the Midwest economy growing at a rate historically consistent with the growth of the national economy; positive values with above-average relative growth (in standard deviation units); and negative values with below-average relative growth.