public static TValue?VariancePopulation <TValue>(this IDataAccess dataAccess, string name, DataAggregate aggregate, ICondition criteria = null, IDataAggregateOptions options = null, Func <DataAggregateContextBase, bool> aggregating = null, Action <DataAggregateContextBase> aggregated = null) where TValue : struct, IEquatable <TValue> => dataAccess.Aggregate <TValue>(name, aggregate, criteria, options, aggregating, aggregated);