From Wikipedia, the free encyclopedia. Phototoxicity, also called photoirritation, is a chemically induced skin irritation, requiring light, that does not involve the immune system. It is a type of photosensitivity. The skin response resembles an exaggerated sunburn.
Contribution margin ratio measures the percentage of sales that would increase net income. To calculate it, divide contribution margin by sales, either in total or per unit: Suppose a gadget selling for $100 per unit brings in $40 per unit of contribution margin.
Home Accounting Courses Financial Ratios Profit Margin Ratio. The profit margin ratio, also called the return on sales ratio or gross profit ratio, is a profitability ratio that measures the amount of net income earned with each dollar of sales generated by comparing the net income and net sales of a company.rofit Margin Ratio. The profit margin ratio, also called the return on sales ratio or gross profit ratio, is a profitability ratio that measures the amount of net income earned with each dollar of sales generated by comparing the net income and net sales of a company.