Which factors will cause the consumption function to shift? Which factors do not cause the function to shift?

The principal factors that will cause the consumption function to shift are: changes in wealth; changes in the price level; and changes in consumer expectations. If wealth increases, then more consumption is possible at the same level of income. If the price level changes, fixed money assets change in value. When prices rise, fixed money assets decrease in value and consumption will decrease. As consumers become more optimistic, they will tend to spend more even if their current income is not changing. The only factor that will not shift the consumption function is disposable income. When disposable income changes, you move up or down a consumption function depending on the direction of change. If disposable income increases, then one moves up along the consumption function.