Development Economics: Evaluate the validity of using National Income statistics as an indicator of standard of living and as a comparison of economic development between different countries. National Income is an indicator of standard of living measured by output, expenditure or income in one year. The reason that these three factors are the chosen methods of calculation is that they can all be calculated fairly easily Ð as long as the data is recorded. The average income in a country determines whether or not people can afford to live ....