Example of a chart showing data with “heavy-tail” distribution
![Example of a chart showing data with “heavy-tail” distribution Line chart showing the distribution of census tract Road Terrain Ruggedness Index values in which low-frequency tracts still tend to have high impact.](/webdocs/charts/108245/fig_5_rugged_terrain_768px.png?v=3857.1)
The intersection of rugged terrain and economic activity remains understudied, so USDA, Economic Research Service researchers developed two classifications of U.S. census tracts: the six-level Area Ruggedness Scale and the five-level Road Ruggedness Scale.
Download higher resolution chart (4267 pixels by 4658, 300 dpi)