Measure slows down report

I have a report with 2 data sources.

DS 1: Layout table that is 'Imported' and came from an excel file.  This merely helps me define the layout and order of my rows:

This is a small sample of my excel file.  For context, this works exactly as I am wanting.

DS 2: 'Direct query' of a fact view from the Data Lake.  I have created a custom column on this table that uses a DAX 'SWITCH' to create a corresponding 'BalanceSheetLayoutSectionID' column in this fact data source that then relates to the Layout table.

Issue:  In order to create the custom calculations needed for my report, I have the following measure:

BalanceSheet = 
VAR _SelectedHeader = SELECTEDVALUE(Layout_BalanceSheet[BalanceSheetLayoutSectionID])

VAR TotalCurrentAssets = CALCULATE([Amount], REMOVEFILTERS(Layout_BalanceSheet), 
                            Layout_BalanceSheet[BalanceSheetSectionLvl2] = "Current Assets")

VAR TotalPropertyAndEquipment = CALCULATE([Amount], REMOVEFILTERS(Layout_BalanceSheet),
                                Layout_BalanceSheet[BalanceSheetSectionLvl2] = "Property and Equipment")

VAR LessAccumulatedDepreciation = CALCULATE([Amount], 'reporting fGeneralLedgerEntries'[MAINACCOUNT] >= 1800000 &&
                                   'reporting fGeneralLedgerEntries'[MAINACCOUNT] <= 1852000)

VAR NetBookValue = TotalPropertyAndEquipment - LessAccumulatedDepreciation

VAR TotalNonCurrentAssets = CALCULATE([Amount], REMOVEFILTERS(Layout_BalanceSheet),
                            Layout_BalanceSheet[BalanceSheetSectionLvl2] = "Other Assets")

VAR TotalAssets = TotalCurrentAssets + NetBookValue + TotalNonCurrentAssets

VAR TotalCurrentLiabilities = CALCULATE([Amount], REMOVEFILTERS(Layout_BalanceSheet),
                                Layout_BalanceSheet[BalanceSheetSectionLvl2] = "Current Liabilities")

VAR TotalNonCurrentLiabilities = CALCULATE([Amount], REMOVEFILTERS(Layout_BalanceSheet),
                                Layout_BalanceSheet[BalanceSheetSectionLvl2] = "Non-Current Liabilities")

VAR LongTermDebtNet = CALCULATE([Amount], REMOVEFILTERS(Layout_BalanceSheet),
                        'reporting fGeneralLedgerEntries'[MAINACCOUNT] = 2750010 ||
                        'reporting fGeneralLedgerEntries'[MAINACCOUNT] = 2700500)

VAR LongTermDebtNetOfUnamoritized = TotalNonCurrentLiabilities - LongTermDebtNet     

VAR TotalEquity = CALCULATE([Amount], REMOVEFILTERS(Layout_BalanceSheet),
                    Layout_BalanceSheet[BalanceSheetSectionLvl2] = "SHAREHOLDERS EQUITY")

VAR Result = SWITCH(TRUE(),
    _SelectedHeader = "TotalCurrentAssets", CALCULATE([Amount], REMOVEFILTERS(Layout_BalanceSheet), 
                            Layout_BalanceSheet[BalanceSheetSectionLvl2] = "Current Assets"),
    _SelectedHeader = "TotalPropertyAndEquipment", TotalPropertyAndEquipment,
    _SelectedHeader = "NetBookValue", NetBookValue,
    _SelectedHeader = "TotalNonCurrentAssets", TotalNonCurrentAssets,
    _SelectedHeader = "TotalAssets", TotalAssets,
    _SelectedHeader = "TotalCurrentLiabilities", TotalCurrentLiabilities,
    _SelectedHeader = "TotalNonCurrentLiabilities", TotalNonCurrentLiabilities,
    _SelectedHeader = "LongTermDebtNetOfUnamoritized", LongTermDebtNetOfUnamoritized,
    _SelectedHeader = "TotalLiabilities", TotalCurrentLiabilities + LongTermDebtNetOfUnamoritized,
    _SelectedHeader = "TotalEquity", TotalEquity,
    _SelectedHeader = "TotalLiabilitiesAndShareHoldersEquity", TotalCurrentLiabilities + LongTermDebtNetOfUnamoritized + TotalEquity,
    [Amount])
    
Return Result

The '_SelectedHeader' allows me to know which line I am on in the report and to appropriately calculate it's value or simply give it the 'Amount', which means it is not a custom calculation.

This works exactly as expected, however, it takes the report matrix 20-25 seconds to get this all loaded.  

I feel like maybe my measure isn't done right or perhaps my data source design is incorrect.  Is there a way to speed this up?