The Manager of the Manufacturing Division of Iowa Windows Does

Essay

The manager of the manufacturing division of Iowa Windows does not understand why income went down when sales went up.Some of the information he has selected for evaluation include:
$$\begin{array} { l r r } & \text { Ianuary } & \text { February } \\\text { Units produced } & 40,000 & 30,000 \\\text { Units sold } & 30,000 & 40,000 \\ & & \\\text { Sales } & \$ 600,000 & \$ 800,000 \\\text { Beginnuing inventory }& 0 & 150,000 \\\text { Cost of production } & 600,000 & 550,000 \\\text { Ending inventory } & 150,000 & 0 \\\text { Operating income } & 70,000 & 35,000\end{array}$$ The division operated at normal capacity during January.
Variable manufacturing cost per unit was $5,and the fixed costs were $400,000.
Selling and administrative expenses were all fixed.
Required:
Explain the profit differences.How would variable costing income statements help the manager understand the division's operating income?