
15. Re: Calculation for Average of an Average over 2 or More Different Periods
Lee Polikoff Jun 25, 2019 7:54 AM (in response to Joe Oppelt)For now, Phase 1 ends at the end of 2016.

16. Re: Calculation for Average of an Average over 2 or More Different Periods
Naveen B Jun 25, 2019 8:00 AM (in response to Naveen B)Lee Polikoff could you please check will this work

17. Re: Calculation for Average of an Average over 2 or More Different Periods
Joe Oppelt Jun 25, 2019 8:02 AM (in response to Joe Oppelt)1 of 1 people found this helpfulAnd here I'm doing it by phase ending at 2016

18. Re: Calculation for Average of an Average over 2 or More Different Periods
Naveen B Jun 25, 2019 8:11 AM (in response to Naveen B)1 of 1 people found this helpfulCalculation for the Multiplephase
Date filter:
Minimised calculation clutter
MIN(IF [Date filter]='P1'
THEN
{Fixed :AVG(
{Fixed DATETRUNC('month', [Flight Month]): SUM(
{fixed DATETRUNC('month', [Flight Month]):SUM(IF [Date filter]='P1' THEN [Flights OnTime] END)}/
{fixed DATETRUNC('month', [Flight Month]):SUM(IF [Date filter]='P1' THEN [Total Flights] END)}
)}
)
}
ELSEIF
[Date filter]='P2'
THEN
{Fixed :AVG(
{Fixed DATETRUNC('month', [Flight Month]): SUM(
{fixed DATETRUNC('month', [Flight Month]):SUM(IF [Date filter]='P2' THEN [Flights OnTime] END)}/
{fixed DATETRUNC('month', [Flight Month]):SUM(IF [Date filter]='P2' THEN [Total Flights] END)}
)}
)
}
END
)
Hope this will understand
BR,
NB

19. Re: Calculation for Average of an Average over 2 or More Different Periods
Lee Polikoff Jun 25, 2019 8:49 AM (in response to Naveen B)I want to thank you both for the help. Unfortunately I can only mark one as the correct answer. I am going to have to select Naveen's response and I'll explain why. Once I had the phase avg's I had to perform additional calculations to get the control limits for the SPC chart. I started with Joe's workbook. When I tried to do calculations against the Overall average of Averages I was getting extra rows added and couldn't get the values I was expecting. I'm sure If I asked Joe he would have provided more assistance to get me down to the data I needed. I then went to Naveen's solution and had no issues getting the values I needed. It was very straight forward. Yes, his LOD calculation needs studying to understand, but it works exactly as I needed.
Here are the different results which led to my decision.
Thanks again for the help