Calculating Moving Average of Percentages in Tableau

0
votes

I have a data set below where I have a percentage of availability by item by month. I want to be able to calculate both a monthly average across items as well as a rolling average. I'm able to successfully create the monthly average but for the rolling average Tableau appears to be taking the monthly averages and just averaging those out to get the rolling average. This isn't correct.

What I need is for Tableau to take all availability percentages for the previous months and calculate the rolling average based on that, rather than taking an average of the previous months' averages.

Any suggestions? Packaged workbook loaded onto dropbox here- https://www.dropbox.com/s/8amt6jnv9ycz6y3/RollingAvg%20-%20Copy.twbx?dl=0

Item    Availability Percentage Month
A   90% 1/1/2017
A   95% 2/1/2017
B   98% 1/1/2017
B   67% 2/1/2017
C   89% 1/1/2017
C   92% 2/1/2017
C   93% 3/1/2017
1
averagetableau-apimoving-average
Read the online help about table calls and pay special attention to the section on partitioning and addressing - Alex Blakemore
There is nothing in the link.. can you check the report - Siva
The comment above should say "table calcs" not "table calls" -- stupid autocorrect ... - Alex Blakemore
@Siva thanks for catching that. I've updated the link to my workbook. - agas22
Is your issue resolved? if not I am not convinced on taking average of percentages, because field is already a percentage on instead it would be better to know the original value and then calculate the montly and rolling percentages. I feel this approach would be more meaningful - Siva

1 Answers

1
votes

If you follow the instructions here on tableau's website, you would be able to get around moving average issue and go beyond to add moving standard deviation based on the period that you select.

https://www.tableau.com/learn/tutorials/on-demand/bollinger-bands