PlanGuru's "Adjust prior period amount" method allows you to forecast based on historical (and projected) amounts and a growth rate. This is perfect when you simply want to grow revenues or expenses by a %.
Under this method there are three sub-options:
1. Adjust by interim period - This option takes the comparable prior period balance and grows it my the percentage defined in the right hand “Year & Adjust %” box.
For example lets look at how PlanGuru calculates the January 2012 amount using this method. PlanGuru takes the comparable prior period balance, January 2011 (in this case 12,345), and grows it by the defined percentage, 2.3% yielding a foretasted amount of 12,629.
2. Adjust prior year amount by annual % - This approach takes the full year amount for the PY, grows it by the defined percentage, and allocates to each month (quarter) based on your seasonality factors.
For example lets look at how PlanGuru calculates the January 2012 amount using this method. Using the full year amount from the prior year, 2011 (181,038) it gets multiplied by our growth rate, then multiplied by the seasonality % for the first period. The result is the projected amount for January of 2012 (16,890).
(seasonality factors are configured during analysis setup, but can be altered by going to Edit>Analysis Setup and clicking the seasonality tab. From there you can update the seasonality profile.)
3. Adjust by period – The approach applies a growth rate to each previous period, for instance in the example below Feb 2012 is a function of Jan 2012 and the defined 5% growth rate. Under this method you can grow each period of the one just previous. PlanGuru also give you the option of selecting the period and starting amount is the adjustment.
For example lets look at how PlanGuru calculates the January 2012 amount using this method. Using the last historical amount from December 2011 (18,745) the amount is grown by 2.5%. The result is the projected amount for January of 2012 (19,214).