John McDonald is the Operations Manager for ABC Chemicals. G2Pass is one of ABC’s most successful products. ABC has to estimate the next year’s expected sales of G2Pass. Sales records of G2Pass over the past two years (8 quarters) are given below:
Year Sales Year Sales
2016Q1 ?75? 2017Q1 ?78 ?
2016Q2 ?95? 2017Q2 ?94 ?
2016Q3 ?120? 2017Q3 ?125?
2016Q4 ?154 ? 2017Q4 ?153?
a. Determine the seasonal factors for each quarter.
b. Use simple moving average to forecast the total sales of 2018 based on the total annual sales of previous years.
c. Forecast the demand for the four quarters of 2018.