If money income stays the same, but the price of one good goes up, the effective purchasing power falls, and vice versa.
Purchasing power is linked with Inflation.
... family size is 3.67. In the town the population is spread out with 30.3% under the age of 18, 8.1% from 18 to 24, 29.9% from 25 to 44, 23.8% from 45 to 64, and 7.9% who ...