- When there is an increase in the income of consumers, the demand for normal goods tends to rise.
- This results in a shift of the demand curve to the right, indicating an increase in quantity demanded at every price level.
- On the other hand, a decrease in income would lead to a leftward shift in the demand curve.

- For inferior goods, an increase in the income of consumers may lead to a decrease in demand as people switch to higher-quality alternatives.
- This shift in preference would cause the demand curve to shift to the left.
- Conversely, a decrease in income could result in an increase in demand for inferior goods, causing the demand curve to shift to the right.

- Luxury goods are highly sensitive to changes in income.
- An increase in income leads to a significant increase in demand for luxury goods, shifting the demand curve to the right.
- Conversely, a decrease in income may lead to a decrease in demand for luxury goods, causing the demand curve to shift to the left.

- Necessity goods have relatively stable demand regardless of changes in income.
- However, an increase in income might lead to a slight increase in demand for these goods, resulting in a slight shift to the right in the demand curve.
- A decrease in income may have a minimal impact on the demand for necessity goods.