Conceptual Difficulties:
• No practicable methods exists for inclusion of some items in National Income (NI), such as — services for which no remuneration is paid, goods that are marketed sold at a price but are used for self-consumption etc.
• It is not always possible to make a clear distinction between primary, intermediate and final goods.
• The price that should be chosen to determine the money value of National product is a difficult question.
• Debate regarding inclusion of income of foreign companies in National Income estimates since, a large part of such income is remitted out of the country.
Statistical Difficulties
• Changes in the price level involve the use of Index Numbers which have their inherent difficulties.
• Official statistics are not always accurate as it is based on guess work and sample survey.
• Methods of computing NI are not the same in all countries.
• The statistical data are often not available.