Forecast returning negative values

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Occasional Visitor

Hello Excel community-thank you for your time and help.  I did a forecast for population and the first figure it forecasted was decreased by almost 2%.  Is that normal?  There were 2 years in the historical data where the population figures decreased.  The rest of the forecasted figures were normal.

2 Replies

Hi Alan

 

We'd really need some more information.

 

Can you expand (be a bit more specific) on what you are doing and what you think the problem is

 

Thanks

 

 

Alan - The URL at the bottom of this message is a good place to start on your forecast math journey. The different forecast functions are described and there is a workbook with examples. I noodled with some existing data and I could change enough data points to force the first period of forecast data be less than the last period of actual but I didn't dig deep enough to understand the math (lunch break is over). Good Luck!

 

https://support.office.com/en-us/article/Forecasting-functions-reference-897a2fe9-6595-4680-a0b0-93e...