A multiplier is a factor that amplifies or increases the base value of something else. In economics, a multiplier is a factor of proportionality that measures how much an endogenous variable changes in response to a change in some exogenous variable). In terms of gross domestic product, the multiplier effect causes changes in total output to be greater than the change in spending that caused it. The multiplier effect provides a numerical value or estimate of a magnified expected increase in income per dollar of investment. There are different types of multipliers, such as fiscal multipliers, deposit multipliers, and equity multipliers. In math, a multiplier is the number by which a multiplicand (another number) is multiplied. A multiplier, along with a multiplicand, helps in finding the product either through repeated addition or multiplication.