This document discusses the importance of measuring a country's economic performance and defines key terms like Gross National Income (GNI). It explains that GNI measures the total market value of all final goods and services produced by the citizens of a country within a given period. It can be measured quarterly or annually using the country's currency. The document outlines different approaches to calculating GNI, such as expenditure, income, and industrial origin approaches. It also distinguishes between nominal/current GNI values and real/constant GNI values adjusted for inflation. Limitations to GNI measurement include non-market activities, the informal sector, externalities, and quality of life factors. Students are assigned questions to answer.