F5 question

mark057

Can someone please give me some direction on the extract of this question?

I've been given 10 quarters of retail sale data: Q1 285 000, Q2 310 000, Q3 315 000, Q4 385 000, Q5 340 000,
Q6 370 000, Q7 375 000, Q8 460 000, Q9 395 000 and Q10, 425 000.

I've also been given a quarterly season index: Q1 94, Q2 98, Q3 96, Q4 112.

Can anyone give me a simple explanation of how I can calculate the value of deseasonalised data from the above?

I don't want to look at the answer before attempting the question but have never calculated seasonal variations froman index like this.

Any help gratefully appreciated.

Mark

SandyHood

Index numbers are the same as decimals x 100

1. So divide the index by 100 to give a decimal
2. divide the actual sales by the decimal to give a
   deseasonalised sales value

mark057

Thanks for the info Sandy.

Could not find anything about this in the study text.

Mark

SandyHood

Look at the syllabus 4 (b)

Explain the use of forecasting techniques including time series, simple average growth models and estimates based on judgement and experience. Predict a future value from provided time series analysis data using both additive and proportional data