771R36. The proportion that the business carried on in Québec is of the aggregate of that carried on in Québec and elsewhere during a taxation year by a grain elevator corporation is one-half of the aggregate of(a) the proportion that the number of metric tons of grain received in the elevators operated by the corporation in Québec is of the total number of metric tons of grain received in all elevators operated by that corporation; and
(b) the proportion that the salaries and wages paid by the corporation to the employees of its establishment in Québec is of the aggregate of all salaries and wages paid by that corporation.