Creating a historical trend with current actuals and forecasting for later months

[Anonymous]

Hi All, 

I have a table with Actuals and forecast from July 2020 to June 2021. 

I also have a Historical trend percentage for each of the 12 months . 

I want to calculate the total actuals from July 2020 to March 2021 and use the total to forecast from July 2020 to June 2021 (12 Months) using the Historical trend percentage .

Then draw a line graph for the historical trend % * forecast 

THe blue line shown in the graph is what I am after and slice it by depatment filter. 

Please note I do have the transaction by each departments. Just shown you below each month actuals has 2 to 3 departments combined. 

Please assist me . 

Ram 

Departments	Month	Actuals	% Historical Trend	Historical Trended
A ,B ,B	July 2020	100	6%	906
A,B,C	August 2020	1,520	8%	1,157
B,C,D	September 2020	200	9%	1,259
C,D,E	October 2020	4,456	9%	1,220
D,F,B	November 2020	2,145	9%	1,245
A ,B ,B	December 2020	322	8%	1,076
A,B,C	January 2021	222	6%	813
B,C,D	February 2021	456	7%	955
C,D,E	March 2021	4,562	8%	1,119
D,F,B	April 2021		8%	1,091
B,C,D	May 2021		9%	1,324
C,D,E	June 2021		13%	1,818
		13,983	Total	13,983

[lbendlin]

@Anonymous You don't really need the historical trend columns.  The historical average can be computed through a measure from the historical actuals.