Finishing RETURN portion for calculating XIRR through multiple variable tables

[Anonymous]

First of all, I found this link quite helpful but did not resolve my issue as I am basically trying to achive something similar:
Solved: XIRR on a dynamic union table - Microsoft Fabric Community

Background:
I am trying to calculate the % difference of IRR based on a time slicer between the original cashflows (baseline) and added cashflows (change) depending on that time slicer.
Therefore, I`m defining tables within a measure to remain dynamic in what rows are selected.
1. Defining a table for baseline cashflow
2. calcualting the IRR  based on 1
3. Defining another table for the change cashflows
4. Union the 1 & 3
5. calculating the IRR based on 4
6. Stuck trying to return the following 


I have built the following measure: 

WAIRR Change = 

var tableWIRR3= SUMMARIZE(tableIRR3,[Asset Scenario ID],[Source Parameter],[IRR base],[total capex base],"WIRR base",[IRR base]*[total capex base])

var tableWIRR2= SUMMARIZE(tableIRR2,[Asset Scenario ID],[Source Parameter],[IRR],[total capex],"WIRR",[IRR]*[total capex])
Return 0 

I need to be returning
(  Sum([WIRR])/Sum([total capex])    -   (Sum([WIRR base])/Sum([total capex base]) )   -1

But cant seem to pull it off with the syntax and I need help checking what syntax to use and that my logic in building this is correct.

I`m also attaching the full code (as a picture, did not want to paste the entire thing in here) of the measure WAIRR Change below as I`m summarizing multiple tables to reach what I have written up.

Any help is much appreciated.


Full code of measure

[lbendlin]

Have you considered using the built-in XIRR function?

XIRR function (DAX) - DAX | Microsoft Learn

[Anonymous]

I am in fact using the XIRR function to calculate IRR for each of my "Asset scenario ID" under each "Source Parameter" at a previous step through this variable: 

var tableIRR3= SUMMARIZE(tablebase2,[Asset Scenario ID],[Source Parameter],"total capex base",SUMX(tablebase2,[Capex]),"IRR base",XIRR(tablebase2,[Cashflow],[Impacted Date]))

What I am trying to do is to calculate the weighted IRR (IRR * Capex) for two sub-sets of the data and visualise the change % between them and hence why 
"
I need to be returning
(  Sum([WIRR])/Sum([total capex])    -   (Sum([WIRR base])/Sum([total capex base]) )   -1
"
Comparing against tables created using the same exact syntax, I can see that the results are correct but I believe it`s SUMX that is re-evaluating and returning results that are not required. 

Please do take a look at the screenshot for the full measure, I would really appreciate help in closing this off. 

Many thanks for your comment.

[lbendlin]

Please provide sample data that covers your issue or question completely, in a usable format (not as a screenshot).
https://community.fabric.microsoft.com/t5/Community-Blog/How-to-provide-sample-data-in-the-Power-BI-...
Please show the expected outcome based on the sample data you provided.

https://community.fabric.microsoft.com/t5/Desktop/How-to-Get-Your-Question-Answered-Quickly/m-p/1447...

[Anonymous]

I have posted a reply but it didn`t go through it seems. 
Anyway, my code is:
"

WAIRR Change =

var tablebase2=

SUMMARIZE(CALCULATETABLE(

   'view view_stress_testing_result',KEEPFILTERS('view view_stress_testing_result'[Baseline/Change]="Baseline"),ALL('view view_stress_testing_result'[Source Fiscal Year])),

    'view view_stress_testing_result'[Asset Scenario ID],'view view_stress_testing_result'[Source Parameter],'view view_stress_testing_result'[Baseline/Change],'view view_stress_testing_result'[Impacted Date],

    "Cashflow",

    SUMX(FILTER(('view view_stress_testing_result'),'view view_stress_testing_result'[Impacted Parameter]="Cashflow"&&'view view_stress_testing_result'[Baseline/Change]="Baseline"),'view view_stress_testing_result'[Value]),

    "Capex",

    SUMX(FILTER(('view view_stress_testing_result'),'view view_stress_testing_result'[Impacted Parameter]="Capex"&&'view view_stress_testing_result'[Baseline/Change]="Baseline"),'view view_stress_testing_result'[Value])

)

var tableIRR3= SUMMARIZE(tablebase2,[Asset Scenario ID],[Source Parameter],"total capex base",SUMX(tablebase2,[Capex]),"IRR base",XIRR(tablebase2,[Cashflow],[Impacted Date]))

var tableWIRR3= SUMMARIZE(tableIRR3,[Asset Scenario ID],[Source Parameter],[IRR base],[total capex base],"WIRR base",[IRR base]*[total capex base])

var tableWAIRR3 = SUMMARIZE(tableWIRR3,[Source Parameter],"Sum WIRR",SUMX(tableWIRR3,[WIRR base]),"Sum Capex",SUMX(tableWIRR3,[total capex base]))

var IRRbase= SUMX(tableWAIRR3,[Sum WIRR])

return IRRBASE

"

Data:

Asset Scenario ID	Asset Scenario	Source Parameter	Impacted Parameter	Source Fiscal Year	Impacted Fiscal Year	Source Date	Impacted Date	Baseline/Change	Stress Direction	Value
1	Asset 1	FX Rates	Cashflow	null	2020	null	01/01/2020	Baseline	null	-922165
1	Asset 1	FX Rates	Cashflow	null	2021	null	01/01/2021	Baseline	null	214134.3
1	Asset 1	FX Rates	Cashflow	null	2022	null	01/01/2022	Baseline	null	416461.4
1	Asset 1	FX Rates	Cashflow	null	2023	null	01/01/2023	Baseline	null	876725.6
1	Asset 1	FX Rates	Cashflow	null	2024	null	01/01/2024	Baseline	null	112972.2
1	Asset 1	FX Rates	Cashflow	null	2025	null	01/01/2025	Baseline	null	668644.6
1	Asset 1	FX Rates	Cashflow	null	2026	null	01/01/2026	Baseline	null	725756.2
2	Asset 2	FX Rates	Cashflow	null	2020	null	01/01/2020	Baseline	null	-520438
2	Asset 2	FX Rates	Cashflow	null	2021	null	01/01/2021	Baseline	null	314378.6
2	Asset 2	FX Rates	Cashflow	null	2022	null	01/01/2022	Baseline	null	223200.7
2	Asset 2	FX Rates	Cashflow	null	2023	null	01/01/2023	Baseline	null	141828.6
2	Asset 2	FX Rates	Cashflow	null	2024	null	01/01/2024	Baseline	null	659425.1
2	Asset 2	FX Rates	Cashflow	null	2025	null	01/01/2025	Baseline	null	119014.1
2	Asset 2	FX Rates	Cashflow	null	2026	null	01/01/2026	Baseline	null	878225.1

Expected results:

1956169

Shown results:

3787783

Which seems like XIRR is re-evaluating based on rows of [Source Parameter] only (where I need IRR to be calcualted for each Source parmater and asset ID underneath), and then for some reason multiplied by 2!