Forecasting Excel

**redrasta** · 09-08-2011, 08:52 AM

Hi,

I have three sets of sales data (week, number of sales) for 2009, 2010 and 2011. I would like to try and use the 2009 and 2010 data combined with the year to date 2011 data to predict sales for the rest of 2011.

Does anybody know which functions or formulas I should use?

Thanks

**alansidman** · 09-08-2011, 08:55 AM

What are your logical assumptions for forecasting? Growth rate? Static? Average of Past? How do you want to calculate it? Can't give you any feedback until we understand your assumptions.

**redrasta** · 09-08-2011, 11:35 AM

I would like to show the same pattern trends. So as this is an event I want to show that the hightened growth that come close to the event as shown in the 09, 10 numbers appears for the 2011 forecast.

Average of past is I guess a way of showing that?

Hope that makes sense.

**pbody** · 09-08-2011, 01:13 PM

Sounds like you might want to use the TREND function. It returns values along a linear trend using the method of least squares to the historical data.