The sloped line, which draws a center path through a cluster of points, indicates a relationship between income and heat-related illness. (A flat line would show no relationship.)
The household median income is determined by the ZIP code where the individual resided in 2017 when they were hospitalized or visited the ER and diagnosed with a heat-related illness.
The rate per 100,000 people was calculated by dividing the number of hospitalizations and ER visits into the estimated population. Each point represents a ZIP code with 10 or more. Select a point to see details.