Profit margin is very hard to compute on an individual item. How do you allocate capital cost, cost of labor, r&d, etc? For instance, a recipe may consist of in

Profit margin is very hard to compute on an individual item. How do you allocate capital cost, cost of labor, r&d, etc? For instance, a recipe may consist of ingredients that cost a few dollars but it may include the work of the chef in crafting the recipe, capital depreciation of the equipment used, space allocation of the restaurant and a million other factors that are though to explicitly account for.