Time series modeling

Do you guys know of a simple way to model events happening at a given moment in time - eg a specific month - without a complicated if/then formula? Let’s take real estate model for an example. Let’s say we have some revenue or cost event happening in Month 6. But we want month 6 to be an assumption and it could be changed to Month8 or Month10 in the assumptions box. Now I know I can put in a formula or an array that says “if current_month is >M6 then … “ but those make the model illegible for anyone but the author. Is there a simpler and more elegant solution?

6 Comments
 

Flags are your friend. Have a flag that toggles every x months (can use mod() per the above comment) and then link your actual calc to the flag. Makes it 1000x more legibile and easy to understand.

Generally I've found having helper calculations, such as time series flags or intermediate outputs, is a lot better than trying to jam a multi-step formula into one cell. 

 
Most Helpful

Thanks. Can you explain this a bit further?  Like if I have my time series Month1-M12

I have a line item that I want triggered but I'd like to toggle when it begins. eg. M 3 or M4, TBD by user.

I can have an assumption tab that has states when the line item begins. But then I get confused. I believe I can do something where there's a row for the month number and then compare than with a >= to the assumptions month, and if so, then put in LineItem.  But this syntax is long and confusing. There should be a simpler way. 

I don't think I really follow your meaning by

Just do a true false - =((current_month)=(input)) * output

And I also don't understand what randwithabando meant by =mod()

example

 

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