The success ratio here is calculated using the following equation, where SR is "Success Ratio": SR = ((% Black-owned firms) * (Median household income)) / 10e5
As we can see much success is concentrated in the DC and Atlanta areas.
This data is used for research with Project New Greenwood -- the project in which we find the city most suited to be the "New Black Wall Street." Some "0" counties (e.g. Ellis county) have otherwise high Success Ratios but have no data associated with them and could not be included.