- 18 Marks
QT – Nov 2018 – L1 – Q6b – Forecasting
Calculate the moving average, trend values, seasonal variation, and forecast membership.
Question
Membership of Pro Amalion, a network of professional volunteers, has grown over the years but in the months of the second quarter, there was always a decline. The table below shows membership records for a period of four years:
| Year | 1st Quarter | 2nd Quarter | 3rd Quarter | 4th Quarter |
|---|---|---|---|---|
| Year 1 | 713 | 694 | 735 | 755 |
| Year 2 | 767 | 733 | 766 | 780 |
| Year 3 | 787 | 755 | 798 | 814 |
| Year 4 | 816 | 790 | 826 | 843 |
Required:
i) Calculate the centered four-quarterly moving average of membership. (4 marks)
ii) Using a least squares trend equation based on (i) above, calculate the trend values. (5 marks)
iii) Using (ii) above, calculate the percentage seasonal variation and the average seasonal variation of membership. (5 marks)
iv) Determine the seasonally adjusted forecast of membership for each of the four quarters of Year 5. (4 marks)
Find Related Questions by Tags, levels, etc.
- Tags: Forecasting, Least Squares, Membership Forecast, Moving Averages, Seasonal Variation, Time series
- Level: Level 1
- Topic: Forecasting
- Series: NOV 2018
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