Functional urban area
The functional urban area (FUA), previously known as larger urban zone (LUZ), is a measure of the population and expanse of metropolitan and surrounding areas which may or may not be exclusively urban. It consists of a city and its commuting zone, which is a contiguous area of spatial units that have at least 15% of their employed residents working in the city.
The FUA represents an attempt at a harmonised definition of the metropolitan area. Eurostat's objective was to have an area from which a significant share of the residents commute into the city, a concept known as the "functional urban region." To ensure a good data availability, Eurostat adjusts the FUA boundaries to administrative boundaries that approximate the functional urban area.