“This map shows the flow of all domestic freight between states in 2015 using data from the Freight Analysis Framework, which is a comprehensive accounting of all commercial freight movement between states by all modes of transportation. This includes freight moved by trucks, trains, planes and pipelines, but excludes foreign imports and exports and freights transported within a state. How to read it: The arrows represent the origin and destination of goods shipped between states. Thicker and darker arrows indicate higher volume (each commodity is scaled relative to the highest volume between any two states, so arrow size isn’t comparable across commodities)…”