Concept:National income statistics measure the total economic output and income of a country over a period.Explanation:These statistics record the value of all goods and services produced in an economy. They are not used to share income equally among citizens or to count the total population directly. One important use is to compare total national income with the population size. This helps in estimating per capita income, which is the average income per person. Per capita income is calculated by dividing national income by the total population: Per capita income=Total populationNational income. Therefore, national income statistics help in estimating how much income each citizen earns on average.Answer:D. Estimate per capita income