SQL Server 2017

By using db<>fiddle, you agree to license everything you submit by Creative Commons CC0.

CREATE TABLE dbo.GL_PeriodPostingHistory (
    Acct INT,
    Year INT,
    Prd INT,
    begbal INT,
    debit INT,
    credit INT
);
INSERT INTO dbo.GL_PeriodPostingHistory
VALUES (1, 2017, 1, -134, 0, 0),
(1, 2017, 10, 0, 0, 20),
(1, 2017, 11, 0, 0, 186),
(1, 2018, 1, -340, 17, 14),
(1, 2018, 4, 0, 0, 7),
(1, 2018, 6, 0, 0, 33),
(1, 2018, 12, 0, 0, 152),
(1, 2019, 1, -529, 0, 0),
(2, 2014, 1, 1000, 0, 0),
(2, 2015, 1, 1000, 0, 0),
(2, 2015, 5, 0, 0, 950),
(2, 2016, 1, 50, 0, 0),
(2, 2017, 1, 50, 0, 0),
(2, 2018, 1, 50, 0, 0),
(2, 2019, 1, 50, 0, 0);
15 rows affected

SELECT
pph.Acct,
pph.Year, 
pph.Prd,
pph.begbal,
pph.debit,
pph.credit,
FIRST_VALUE(pph.begbal) OVER (PARTITION BY pph.Acct ORDER BY pph.Year, pph.Prd)
	+ SUM(pph.debit-pph.credit) OVER (PARTITION BY pph.Acct ORDER BY pph.Year, pph.Prd) AS endbal
FROM dbo.GL_PeriodPostingHistory pph;


Acct
Year
Prd
begbal
debit
credit
endbal


1
2017
1
-134
0
0
-134

1
2017
10
0
0
20
-154

1
2017
11
0
0
186
-340

1
2018
1
-340
17
14
-337

1
2018
4
0
0
7
-344

1
2018
6
0
0
33
-377

1
2018
12
0
0
152
-529

1
2019
1
-529
0
0
-529

2
2014
1
1000
0
0
1000

2
2015
1
1000
0
0
1000

2
2015
5
0
0
950
50

2
2016
1
50
0
0
50

2
2017
1
50
0
0
50

2
2018
1
50
0
0
50

2
2019
1
50
0
0
50

Acct	Year	Prd	begbal	debit	credit	endbal
1	2017	1	-134	0	0	-134
1	2017	10	0	0	20	-154
1	2017	11	0	0	186	-340
1	2018	1	-340	17	14	-337
1	2018	4	0	0	7	-344
1	2018	6	0	0	33	-377
1	2018	12	0	0	152	-529
1	2019	1	-529	0	0	-529
2	2014	1	1000	0	0	1000
2	2015	1	1000	0	0	1000
2	2015	5	0	0	950	50
2	2016	1	50	0	0	50
2	2017	1	50	0	0	50
2	2018	1	50	0	0	50
2	2019	1	50	0	0	50