Data Storytelling and Dataviz Approach
I chose to look at this week's data over time and by state. In an effort to normalize the data against the population of the states (states with larger populations will undoubtedly have more registrations), I brought in an additional dataset with estimated populations by state, and then calculated the per capita number of registrations. I represented this metric as individual line graphs in a tile map - where each tile represents an individual state.
Similar to how the per capita calculation normalizes for population, the tile map normalizes for the size of the state. By tiling the states in their relative geographic positions, it avoids misrepresenting or inadvertently hiding data due to the size of a state.
A parameter control drives which type of vehicle is represented in the data, and also highlights the vehicle type in the viz in tooltip. This viz in tooltip is a simple bar graph, showing the number of registrations by vehicle type for the state and year hovered over in the main viz.
If you'd like to see what you can visualize with this data, post your work to Tableau Public and Twitter with the hashtag #ThrowbackThursday, tagging @TThrowbackThurs. We'd really love to see what you can come up with!
This week's dataset comes from the U.S. Department of Transportation - Federal Highway Administration. Please be sure to cite the source on your viz.