Economists experience difficulties in accurately measuring income inequality because of which of the following? Choose one or more: A. The Gini index calculation discriminates against the poor in developed economies. B. Government programs are inefficient and difficult to monitor. C. large, underground economies that lack the reporting of income to the government D. Measurements tend to use "before tax" income, not "after tax" income (disposable income), which is the income people actually have available to purchase goods and services. E. The population size of an economy impacts the distribution of data, causing large economies to show more inequality than smaller economies. F. do-it-yourself production of goods and services (such as growing own food or making own clothing) that are not bought or sold in the market G. in-kind transfers where goods and services are given as aid to the poor instead of cash