One-Health Consensus Reference Annotation Checklist (OH-CRAC) CRAC 4.7. Data aggregation This section describes how aggregate data and population totals were generated from the data collection or lower-level aggregates. It includes summing data for records sharing certain characteristics (e.g. aggregation of data by demographic or geographic classifications), determining measures of average and dispersion, and applying weights from sub-process 4.6 (Weighting of records) to derive appropriate totals. In the case of statistical outputs, which use sample surveys, sampling errors corresponding to relevant aggregates may also be calculated in this section.