Cash Management - Forcasting

Alex301286

Hi,

I am currently working on moving averages and would like some assistance with the second part of the question. I am fine with working out the trend and monthly variation.. but coming unstuck with the future forcasting.

Heres what I have...

3 point moving average and figures are...

Sales Vol Trend Monthly Var.
Aug 72,100 - -
Sept 49,600 62,500 (12,900)
Oct 65,800 66,000 (200)
Nov 82,600 69,500 13,100
Dec 60,100 - -

monthly variation for october is (200) units.

The selling price has been set at 14.50

Monthly purchases are estimated to be 30% of the value of the forcast sales

Forcast Trend Variation Forcast Sal Vol. Forcast Sal. Forcast Pur.
Jan

i'm reading through the BPP books and my understanding is that you take the last trend and subtract from the first and divide by the number of trend months you have...

69,500-62,500/3 = 2,333.33

Then add this on to the last sales figure you have from December. But of those of you who know the answer you can tell i'm waaaaayyy off!! If anyone could please give me an idea of what i need to do it would be much appreciated.

Thank you,