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.
The contribution margin ratio is the difference between a company's sales and variable expenses, expressed as a percentage. The total margin generated by an entity represents the total earnings available to pay for fixed expenses and generate a profit.
DEFINITION of 'Dependency Ratio'. A measure showing the number of dependents (aged 0-14 and over the age of 65) to the total population (aged 15-64). Also referred to as the total dependency ratio. Calculated by: