Explaining time variation in geographic price dispersion

The pattern of price dispersion significantly varies over time and across locations. Using a detailed dataset with product-level retail prices, we examine the role of time-varying factors in shaping the time variation of price dispersion. We find that price dispersion variation in an integrated region is mainly driven by oil prices, while the variation in a segmented region is attributed to dispersion in real income. We also find that dispersion in value-added tax rates explains a significant portion of price dispersion fluctuations in both geographic dimensions. This paper offers new evindence on the trade-off that exists for the role of time-varying factors as contributors to price dispersion variation by highlighting their relative importance across different dimensions of economic geography.