Household income by ZIP. Every ZIP is colored by its own real
median income on a 16-step spectrum, low (violet/blue) to high (orange/red). Drag the
range slider below to select an income band (left = bottom, right = top): ZIPs inside
the band stay fully bright, everything outside is merely darkened for context. Push the
sliders to the far ends ($0 β $200k+) and no ZIP is darkened β you see the whole map.