Forecasting

[KJ]

I've got 3 periods worth of historic data and would like to predict the next period. I've checked the help facility and it is asking for known _y's and known_x's. What would these be?

Thanks

[swaink]

KJ

You need headers for each period of data ie 1,2,3 & 4

Using forecast the X is the period you are projecting(4)the known Y's are the data in the rows of data from col 1 to 3 and the known X's are the headers 1 & 2 & 3

doe's that help

[KJ]

swaink

Thanks for you reply.
I put my data into 3 columns headed period1,period2,period3 and period4 (with the period4 column blank).
This resulted in #VALUE! Am I missing something?

Many thanks

KJ

[Joe Was]

Yes,
Your lables are whats confusing you.

Period1 is X=1
Period2 is X=2
Period3 is X=3
and Period4 is X=4
Then the values for Period1..4 is the Y value.
Period1 is Y=Value, etc. JSW

[KJ]

Thanks JSW

I've tried that and it works!
The only thing is - I'm getting loads of negative values!!

If this is the way the business will be going I might as well quit now!!

Please help

Thanks

KJ

[Joe Was]

you may wish to try this:

=GROWTH(sales,,{5},)

where "sales" is a insert-name-define (named range) that contains your data. In your case "sales" is the values for periods1...4. The {5} is an arry for the future period you want to project to. The formula above will tell you the sales you can expect in month 5 if you have the sales values for periods 1 to 4 loaded in range "sales." It can just as well predict the 16th period or periods {6,7}, that is periods 6 and 7 in the same cell. Remember to format the cell. JSW

[KJ]

Hi JSW

Thanks for your replies - it's all sorted now. You've been a great help.

KJ