The document discusses different models for banding local authorities for the purposes of library licensing and services. It considers using total population, active borrowers, and registered readers as metrics for banding. Total population could represent potential user base but is not very informative on its own. Active borrowers potentially represent real users and range from 13-57% of the population across authorities. Registered readers data is inconsistent, ranging from 10-104% of populations across authorities. Other measures like financial strength and materials acquisition budgets are discussed as alternatives. Examples of banding different local authorities using different metrics are provided.