Historical demand for a product is as follows.

Demand April 60 May 55 June 75 July 60 August 80 September 75

a. Using a simple four-month moving average, calculate a forecast for October.

b. Using single exponential smoothing with α = 0.2 and a September forecast = 65, calculate a forecast for October.

c. Using simple linear regression, calculate the trend line for the historical data. Let’s say the X axis is April = 1, May = 2, and so on, while the Y axis is demand.

d. Calculate a forecast for October using your regression formula.

TW-111