Final answer:
Several factors can shift aggregate demand, including changes in consumer and business confidence, government policy, and external events like pandemics, which affect workforce availability and disrupt supply chains.
Step-by-step explanation:
Factors that might shift aggregate demand include changes in consumer behavior, such as a loss of business confidence or a decrease in consumer confidence, which can cause aggregate demand to shift left. Other factors include changes in government policy, such as an increase in taxation or a decrease in government spending, and international factors like imports. External shocks to the economy, such as a pandemic like COVID-19, can also affect aggregate demand by reducing the workforce and causing worker shortages, thereby disrupting production and supply chains. This can lead to a reduction in the consumption component of aggregate demand, as there are fewer goods and services available, and people might also save more due to uncertainty.
Additionally, technological innovation might not directly shift aggregate demand, but it can lead to higher levels of productivity, which could shift aggregate supply instead and indirectly affect aggregate demand through changes in income and employment.