MySQL 8.0

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CREATE TABLE mytable(
   cus_id         INTEGER  NOT NULL 
  ,due_date       DATE  NOT NULL
  ,principal      INTEGER  NOT NULL
  ,disbursed_date DATE  NOT NULL
);
INSERT INTO mytable(cus_id,due_date,principal,disbursed_date) VALUES (1,'2022-01-01',10,'2021-11-01');
INSERT INTO mytable(cus_id,due_date,principal,disbursed_date) VALUES (1,'2022-02-01',10,'2021-11-01');
INSERT INTO mytable(cus_id,due_date,principal,disbursed_date) VALUES (1,'2022-03-01',10,'2021-11-01');
INSERT INTO mytable(cus_id,due_date,principal,disbursed_date) VALUES (2,'2022-03-15',20,'2022-02-15');
INSERT INTO mytable(cus_id,due_date,principal,disbursed_date) VALUES (1,'2022-04-01',10,'2021-11-01');
INSERT INTO mytable(cus_id,due_date,principal,disbursed_date) VALUES (3,'2022-04-01',15,'2022-03-20');
INSERT INTO mytable(cus_id,due_date,principal,disbursed_date) VALUES (2,'2022-04-15',20,'2022-02-15');
INSERT INTO mytable(cus_id,due_date,principal,disbursed_date) VALUES (3,'2022-05-01',15,'2022-03-20');
INSERT INTO mytable(cus_id,due_date,principal,disbursed_date) VALUES (2,'2022-05-30',20,'2022-02-15');
INSERT INTO mytable(cus_id,due_date,principal,disbursed_date) VALUES (1,'2022-05-30',10,'2021-11-01');
INSERT INTO mytable(cus_id,due_date,principal,disbursed_date) VALUES (3,'2022-06-01',15,'2022-03-20');
INSERT INTO mytable(cus_id,due_date,principal,disbursed_date) VALUES (2,'2022-06-15',20,'2022-02-15');
INSERT INTO mytable(cus_id,due_date,principal,disbursed_date) VALUES (2,'2022-06-30',20,'2022-02-15');
INSERT INTO mytable(cus_id,due_date,principal,disbursed_date) VALUES (3,'2022-07-01',55,'2022-03-20');

date_as_of	outstanding
2022-01-01	40
2022-02-01	30
2022-03-01	120
2022-03-15	100
2022-04-01	175
2022-04-01	175
2022-04-15	155
2022-05-01	140
2022-05-30	110
2022-05-30	110
2022-06-01	95
2022-06-15	75
2022-06-30	55
2022-07-01	0