# Demand data

- https://en.wikipedia.org/wiki/Transportation_forecasting
- https://data.seattle.gov/Transportation/2016-Traffic-Flow-Counts/f22b-ywut
	- counts per aterial

## Depicting

Axes:
- time
- source/destination neighborhood or border
- mode choice
- number of trips

Fix a time, then show a bunch of directed arrows between neighborhood polygons.
Line thickness relative to number of trips. Color coding... if you're
interested in a particular neighborhood, vary all the line colors based on
src/dst.