A computer system includes a data storage device. The data storage module receives, stores, and provides access to historical claim data. A categorical aggregation component comprising program instructions stored in a program memory provides categorized and aggregated historical claim data by identifying claim categories based on the historical claim data, each of the one or more claim categories associated with a respective set of claim characteristics, identifying claims of the historical claim data associated with one of the claim categories, assigning each identified claim to one of a plurality of total severity ranges based on the total severity of the identified claim, and determining an average cost per claim year for claims of each total severity range when executed by a computer processor.