↑ Algebraically, this means C = f ( Y d ) {\displaystyle C=f(Y_{d})} where f : R + → R + {\displaystyle f\colon \mathbb {R} ^{+}\to \mathbb {R} ^{+}} is a function that maps levels of disposable income Y d {\displaystyle Y_{d}} —income after government intervention, such as taxes or transfer payments—into levels of consumption C {\displaystyle C} .
