SQL Server 2022

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DECLARE @MyTransactions TABLE (
    [Name] nvarchar(10),
    [Date] datetime2,
    [Debit] decimal,
    [Credit] decimal
 )
 
 INSERT INTO @MyTransactions ([Name],[Date],[Debit],[Credit]) VALUES ('A','2021-01-01',10,0)
 INSERT INTO @MyTransactions ([Name],[Date],[Debit],[Credit]) VALUES ('A','2021-02-01',11,0)
 INSERT INTO @MyTransactions ([Name],[Date],[Debit],[Credit]) VALUES ('A','2021-03-01',0,50)
 INSERT INTO @MyTransactions ([Name],[Date],[Debit],[Credit]) VALUES ('A','2021-04-01',30,0)
 
 INSERT INTO @MyTransactions ([Name],[Date],[Debit],[Credit]) VALUES ('B','2021-01-01',10,0)
 INSERT INTO @MyTransactions ([Name],[Date],[Debit],[Credit]) VALUES ('B','2022-02-01',0,12)
 INSERT INTO @MyTransactions ([Name],[Date],[Debit],[Credit]) VALUES ('B','2022-03-01',0,50)
 INSERT INTO @MyTransactions ([Name],[Date],[Debit],[Credit]) VALUES ('B','2024-04-01',3,0)
 
 
 DECLARE @MyGroups TABLE (
    [Name] nvarchar(10),
    [Year] int,
    [Month] int
 )

select Name,DATEPART(YEAR,[date]) [Year],DATEPART(MONTH,[Date]) [Month],
  SUM(Credit-Debit) OVER(PARTITION BY NAME ORDER BY DATEPART(YEAR,[date]) ,DATEPART(MONTH,[Date])) Balance
  from @MyTransactions

Name	Year	Month	Balance
A	2021	1	-10
A	2021	2	-21
A	2021	3	29
A	2021	4	-1
B	2021	1	-10
B	2022	2	2
B	2022	3	52
B	2024	4	49