SumWithSelectorMethods = new Dictionary<Type, MethodInfo>
            {
                { typeof(decimal), getSumOrAverageWithSelector<decimal>(nameof(Queryable.Sum)) },
                { typeof(long), getSumOrAverageWithSelector<long>(nameof(Queryable.Sum)) },
                { typeof(int), getSumOrAverageWithSelector<int>(nameof(Queryable.Sum)) },