SQL recursive calculate based on previous calculation

Say we have the following SQL Server table

date, qty, debit

I want to calculate a NewDebit value based on the formula shown here. I have tried everything - grouping, partition, cte - it is just not happening...

Anything I try is either a recursive CTE, or partition by, it seems I can't get the previous sum of the calculated results.

See example

with  trng as( -- ordering for recursive sequentially process table 
  select *,row_number()over(order by dt)rn from test
)
,r as( -- anchor - first row
  select 0 as lvl,t.dt, qty,debit,rn
       ,cast(0.0 as float) tsum
       ,debit as newdebit
       ,cast('0' as varchar(100)) expr
       ,formula,testvalue
  from trng t
  where rn=1
  union all
  select r.lvl+1 lvl,t.dt, t.qty,r.debit,t.rn
    ,(r.newdebit+r.tsum) tsum    -- cumulative sum
    ,(r.newdebit+r.tsum)/t.qty newdebit -- partial sum
   -- for debug and clarity
    ,cast(concat(r.expr,'+',r.newdebit) as varchar(100)) expr
    ,t.formula,t.testvalue
  from r inner join trng t on t.rn=(r.rn+1)

)
select dt,qty,debit,newdebit,lvl,rn,tsum
  ,concat('(',expr,')/',qty) exprn
  ,formula,testvalue
from r

Output is

with test data

create table test (dt date, qty int, debit float,formula varchar(100),testValue float);
insert into test values
 ('2024-02-01',5,100,'100','100')
,('2024-02-02',8,150,'100/8',12.5)
,('2024-02-03',3, 50,'(100+12.5)/3',37.5)
,('2024-02-04',6,120,'(100+12.5+37.5)/6',25)
,('2024-02-05',4, 80,'(100+12.5+37.5+25)/4',43.75)
;