Complex Dax Query Help

// Calculate the period use for each day of use, looking ahead by the number of replenishment days for the product's class
	var _PeriodUsage = 
	filter(
	KEEPFILTERS(
	SUMMARIZECOLUMNS(
	//Products[SalesCode],
	//'Flowline Stations'[StationId],
	'Station Component Stock'[StationStockControlId],
	Dates[Date],
	_ReplenishmentPeriod,
	_UpperBound,
   	_LowerBound,
   	_UsageClass,
   	_C_ClassReplen,
   	_B_ClassReplen,
   	_A_ClassReplen,
   	"DailyUsage", sum('Flowline Station Usage'[DailyUsage]),
   	"PeriodUsage", [Period Usage]
   	)
   	),
   	not(ISBLANK([DailyUsage]))
   	)


// Rank each period use for a product at a station Asc and Desc
	var _RankedUsage =

		ADDCOLUMNS(
				'_PeriodUsage',
				"Rank",
				RANKX(filter(_PeriodUsage, 'Station Component Stock'[StationStockControlId] == EARLIER('Station Component Stock'[StationStockControlId])), [PeriodUsage],,asc, dense),
				"ReverseRank",
				RANKX(filter(_PeriodUsage, 'Station Component Stock'[StationStockControlId] == EARLIER('Station Component Stock'[StationStockControlId])), [PeriodUsage],,desc, dense)
				)
			table _RankedUsageTbl = _RankedUsage	
			
// Find the rank at the 95th percentile of all ranks for each StationStockControlId
	table _ThresholdRank =
	
	ADDCOLUMNS(
	FILTER(_RankedUsage,
	[ReverseRank] == 1),
	"ThresholdRank", roundup([Rank]*0.95, 0)
	)
	
// **Missing Step** - Create a list of Period Usage for each StationStockControlId where the rank = the 95%ile rank above	

	

Hi Greg_Deckler 

Thank you for the response. I did reply the other day but I've revisited this topic and my latst post is missing? I even received a badge after I sent the reply so no idea how it disappeared!

Anyway, re-writing the reply below:

I'll provide a streamlined part of the query that focuses on the important part. Basically here's waht I'm trying to do:

For each StationStockControlId, Rank the PeriodUsage

Find the Rank at the 95th percentile potision for all PeriodUsage values for each StationStockControlId

Return a list with 1 row per StationStockControlId showing the value at the 95th percentile rank

the below query starts with calculating _PeriodUsage, I've provided a sample output from _PeriodUsage which will let the rest of the query run:

The part that has me stumped is how I can filter _RankedUsage by the results of _ThresholdUsage. If I was using sql this would be a join on StationStockControlId and Rank.

Ultimately, I am looking to get the PeriodUsage for each StationStockControlId where the PeriodUsage is ranked at the 95th percentile of all PeriodUsages for that StationStockControlId. If there is a better way to get the end result in DAX than the way I am trying, please advise!

Thanks