SQL Server 2022

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CREATE TABLE #TEMP
(
    PlanID NVARCHAR(10)
    ,EEID NVARCHAR(15)
    ,Ticker NVARCHAR(10)
    ,MarketValue MONEY
    ,TotalBalance MONEY
    ,CurrentDenominator MONEY
    ,AllocationAmount DECIMAL(18,6)
)

INSERT INTO #TEMP VALUES
('10241299',    '70973',    'VEMAX',    5654.12,    241781.86,  241781.86,  1),
('10241299',    '70973',    'VMGMX',    5972.14,    241781.86,  236127.74,  1),
('10241299',    '70973',    'VTMGX',    35099.02,   241781.86,  230155.6,   1),
('10241299',    '70973',    'VTSAX',    45529.07,   241781.86,  195056.58,  1),
('10241299',    '70973',    'VFIAX',    149527.51,  241781.86,  149527.51,  1)

SELECT
    PlanID 
    ,EEID 
    ,TotalBalance 
    ,Ticker
    ,MarketValue 
    ,AllocationAmount
    ,IncrementedSourceRatio = MarketValue/(TotalBalance - sum(MarketValue) over(order by MarketValue rows unbounded preceding)+MarketValue)
    ,rn = row_number() over(order by MarketValue) 
INTO #TEMP2
FROM #TEMP;

with rcte as (
    select *
      ,cast(IncrementedSourceRatio * AllocationAmount as DECIMAL(10,9)) AdjustedAllocation
      ,cast(0 as DECIMAL(10,9)) cumulAA
    from #temp2 
    where rn=1

union all

select t2.*
      ,cast(t2.IncrementedSourceRatio * (t2.AllocationAmount - rcte.cumulAA - rcte.AdjustedAllocation) as DECIMAL(10,9))
      ,cast(rcte.cumulAA + rcte.AdjustedAllocation as DECIMAL(10,9))
    from rcte
    join #temp2 t2 on t2.rn= rcte.rn+1
  )
select *
from rcte
order by MarketValue

PlanID	EEID	TotalBalance	Ticker	MarketValue	AllocationAmount	IncrementedSourceRatio	rn	AdjustedAllocation	cumulAA
10241299	70973	241781.8600	VEMAX	5654.1200	1.000000	0.0233	1	0.023300000	0.000000000
10241299	70973	241781.8600	VMGMX	5972.1400	1.000000	0.0252	2	0.024612840	0.023300000
10241299	70973	241781.8600	VTMGX	35099.0200	1.000000	0.1525	3	0.145193290	0.047912840
10241299	70973	241781.8600	VTSAX	45529.0700	1.000000	0.2334	4	0.188329030	0.193106130
10241299	70973	241781.8600	VFIAX	149527.5100	1.000000	1.0000	5	0.618564840	0.381435160