This document proposes a quantitative methodology for evaluating the size and comprehensiveness of an integrated data repository (IDR). It describes developing measures across different levels, from raw data sources up to aggregated views, to assess aspects like clinical scope, temporal coverage, and included data types. Examples are provided of IDRs at different medical organizations. The goal is to facilitate monitoring improvements over time or comparisons between IDRs in a way that is intuitive and does not weight some data types over others. The results would provide snapshots of IDRs that characterize their capabilities for clinical and research users.