The goods for which demand increases proportionally less than income, are known as:

An inferior good is a good whose quantity demanded decreases when consumer income rises (or quantity demanded rises when consumer income decreases). In economics, a luxury good (or upmarket good) is a good for which demand increases more than proportionally as income rises Necessity Goods are those goods for which demand increases proportionally less than income A normal good is a good or service that experiences an increase in quantity demanded as the real income of an individual or economy rises. A normal good is defined as having an income elasticity of demand coefficient that is positive but less than one. A good can also be classified as a luxury good or inferior good.