Seasons per period

[Former Member]

Forecasting experts,

There is a section in Univariate forecast profile - Periods (Periods per Season),

SAP says usually this number is 12. But what if forecasting in done using Weekly buckets/weekly level? In this case 52 is more appropriate? Or is this the number of seasons in a year which could be even 1. What i put here? 52 or 12 or 1? How can this value affect when used in a seasonal model or a trend model?

[Former Member · Accepted solution]

The "number of periods" setting means "how many periods I have to wait until history repeats itlself"

Therefore, the important point is what is the seasonality of your data:

- if you plan in months and the history repeats itself every 12 months, put 12 as your seasonal periods.

- if you plan in weeks and the history repeats itself every 12 months... then you should put something like 52.

But some years you will have to correct for the extra week: there is a BADI to modify history before the forecast execution.

In case of a monthly seasonality, I would suggest you stay in the first scenario and eventually manage the weeks with time dissagregation.

regards,

PAblo

[Former Member · Accepted solution]

Pablo,

Thanks for answering this. We are planning in weeks, hence I think we should go for 52 in the period per season field. Do you by chance know how this parameter will affect if it will, the trend test when we use Auto model selection procedure 2 ?

Thanks again for your answer.

KW

[Former Member · Accepted solution]

You probably have gotten your answer already by now...but..as far I know the number of periods in a season will not affect any procedure pr part of the procedure that is not doing test for seasonality. Only when the auto model performs a seasonality test then this will affect. Let me know what you've found out.

[josnestor_cavalcantecerqu]

James,

In my case I have the next situation: I plan in weeks, but my historical data it is in days (now I have two years of historical), repeat each month, like I notice, then which numbers of periods can I use in this case?

Regards

Nestor