Raga Idrees Abdoon2017-11-192017-11-192014-12-22http://hdl.handle.net/123456789/7946Abstract In this paper two disaggregate methods of forecast are compared namely, Cohort component method, and ARIMA method. The comparison is made with respect to the effect of age group length and status of population on the precision of the forecast. The age group lengths considered are5 years, 10 years and 15 years. The important conclusion to arrive at when applying these methods is that the precision of forecast declines with increase in age group length, and as expected, forecast for more developed region is the most precise. Key word: disaggregate forecast, age group lengthdisaggregate methods