The overlap, by drive time
Both footprints routed on the road network. “Both” is the population that can reach a Baskin-Robbins and a Dairy Queen within the same drive time.
| Drive time | Baskin-Robbins reach | Dairy Queen reach | Both | % of Baskin-Robbins | % of Dairy Queen |
|---|---|---|---|---|---|
| 5 min | 73,897,786 | 55,373,243 | 18,380,165 | 24.87% | 33.19% |
| 10 min | 154,128,008 | 152,490,941 | 91,225,200 | 59.19% | 59.82% |
| 15 min | 196,146,271 | 214,078,082 | 152,259,546 | 77.63% | 71.12% |
| 30 min | 250,127,447 | 292,362,576 | 238,244,266 | 95.25% | 81.49% |
| 60 min | 291,965,981 | 320,110,416 | 286,433,821 | 98.11% | 89.48% |
What it means
At 30 minutes, 95.25% of the people Baskin-Robbins can reach are also inside a Dairy Queen catchment. 11,883,181 people are Baskin-Robbins's alone.
A high shared percentage is not automatically bad. It means the two chains have solved the same geography. It matters when one of them is planning to add units: incremental reach comes from the exclusive population, not the shared one.
Narrative Geo does not sample. Every trade area is routed on the actual road network with OSRM, against full Census/ACS population and a maintained POI set. The drive-time matrix is precomputed at 1.08 billion rows, so a national query across a 20,000-store chain returns in seconds rather than being metered per location.