calculate average per category per year

[Anonymous]

hello,

New to power bi here and would appreciate some help. 

I want to calculate the average of units per year for apo key and material key (which make a distinct category) for my data. 

For certain purposes the average needs to be calculated for previous year, current year and next year which are denoted by 'PY', 'CY' and 'NY' in a column marked 'IS YEAR'. 

the column highlighted is what i need to obtain. 

I have tried using this- 

Avg =

CALCULATE (

AVERAGE (z[units] ),

FILTER (z, z[material key]=EARLIER(z[material key]))

)

which is calculating the average based on apo key and material key but the average does not change for different years.

can someone provide help with this.

Thanks 🙂

[Anonymous]

hey! 

the calculation of the average went well. but now i'm stuck at calculating standard deviation of units per category (apo key+ material key) per year which is PY,CY and NY

I understand simply using the stdev.p wouldnt work as it computes based on the formula SUM(X-Xavg)^2/n and  n keeps changing per category per year.

is using stdevx.p a better apporach? 

if so, then what would be the expression for it so that standard deviation is obtained per category per year?

thank you 🙂

[HotChilli · Accepted solution]

You're nearly there.  You just have to add in the other conditions (which you have described) in to the filter.

e.g.  && z[apo key] = EARLIER (z[apo key])

and the same for year.

Edit: the CY, NY and PY are irrelevant because you have the Year pre-calculated . Can you confirm?

[Anonymous]

Yep that works 🙂 

i really dont understand how i missed this small step. 

Looks like i need to take a break.

But thanks a tonne