Factors that can shift the aggregate demand curve?

Since modern economists calculate aggregate demand using a specific formula, shifts result from changes in the value of the formula's input variables: consumer spending, investment spending, government spending, exports, and imports

"social stratification refers to the way people are ranked and ordered in society. in western societies, stratification is primarily seen and understood as a result of socioeconomic status, which produces a hierarchy in which access to resources, and possession of them, increases from the lower to the upper strata"