Figure 4
The image contains two maps of the United States side by side. The map on the left shows population clusters by county in 2021, while the map on the right shows GDP clusters by county in 2021 in thousands of dollars. Both maps use a color-coded legend to indicate different types of clusters: High-High, High-Low, Low-High, Low-Low, and areas with no significant clusters. The maps highlight regions with significant spatial autocorrelation in population and GDP, with a threshold for significance set at a p-value of less than 0.1 percent. The maps reveal patterns of economic and demographic clustering across the country.Local Moran Index cluster map; population by county in 2021 (on the left) and current 2021 dollar GDP by county (on the right, in thousands of dollars). Threshold for significance: p-value < 0.1%