How to I Create Quartiles based on Different Groupings?

Hello,

I have a dataset that looks like this:

I have a lot more Times, Classes, Subclasses, SKUs, and Vendors.

First, I want to calculate the first and third quartiles:

I did so by creating a measure by the following:

Quartile1 = SUMMARIZE(dataset, dataset[Class1],dataset[Class2],dataset[Subclass1], dataset[Subclass2],"Q1", PERCENTILE.INC(dataset[rate],0.25))

But I get the following error: "The expression refers to multiple columns. Multiple columns cannot be converted to a scalar value."

I've tried similar measures also, but when it works, it's not grouping the Quartiles like I want it to.

The Ideal end result is to make a table that looks like this for all the different Times, Classes, and Subclasses:

where

IQR = Quartile1 - Quartile3

Lower_Limit = Quartile1 - (1.5*IQR) and

Upper_Limit = Quartile3 + (1.5*IQR)

I would like to dynamically calculate the Quartiles for the different Time, Classes, and Subclasses.

My end goal is to look at a particular SKU and identify whether or not that SKU is below the Lower_Limit or above the Upper_Limit.

Thank you for your help. I am not as familiar with DAX and have been stuck on this for a while.