The multiplier process is the idea that an increase in AD because of an increased injection
A negative multiplier effect can also occur i.e. a withdrawal from the economy could lead to an even further fall in income, decreasing economic growth and possibly leading to a decline in the economy. This means that government plans to cut deficits will lead to an even further decrease of the economy.
formular for the multiplier
Marginal propensity to consume is how much consumers will spend if given an additional £.