Constant Gross Margin Rate
This method assumes that every product contributes an equal percentage of gross profit for every shilling of sales. It works back from gross margin to the joint costs allocation. It includes the given steps:
(i) Compute the overall rate of gross margin for every the products
(ii) Multiply the computed overall rate with the sales of every product to receive the gross margin of the product.
(iii) Deduct the gross margin from the sales value of the product to find out the net costs for each product.
(iv) Deduct separable costs from the net costs to receive joint costs allocated.