A socio-ecological system consists of 'a bio-geo-physical' unit and its associated social actors and institutions.
Contribution Margin. Contribution margin is a productâs price minus all associated variable costs, resulting in the incremental profit earned for each unit sold. The total contribution margin generated by an entity represents the total earnings available to pay for fixed expenses and to generate a profit. The contribution margin concept is useful for deciding whether to allow a lower price in special pricing situations.
The quantity, , is of interest in its own right, and is called the Unit Contribution Margin (C): it is the marginal profit per unit, or alternatively the portion of each sale that contributes to Fixed Costs. Thus the break-even point can be more simply computed as the point where Total Contribution = Total Fixed Cost: