Translating business information requirements into a data model is not always a straightforward task. Certain business information does not always fit into the data model when standard data modeling rules and principles are used. A data model embodies a comprehensive understanding of the business information requirements; enables effective communication among designers, developers, and users; and forms the basis for designing correct, consistent, shareable, and flexible databases. Derived business information is usually avoided by most data modelers because of its tendency to become redundant. Summary-level entities in which all data elements are derived may occur when business information from outside the data model’s scope is received at an aggregate level. A data model promotes a comprehensive understanding of the business information requirements. Historical business information is a type of time-dependent business information, but its focus is different. An organization must understand what the business information that originates from an external organization actually represents.