WITH SUB1 AS (SELECT YEAR_MONTH, MONTH_AMT,
SUM(MONTH_AMT) OVER(ORDER BY YEAR_MONTH ROWS BETWEEN UNBOUNDED PRECEDING AND CURRENT ROW) AS CUML_AMT
FROM (SELECT SUBSTRING(SALES_DATE, 1, 7) AS YEAR_MONTH,
SUM(SALES_AMT) AS MONTH_AMT
FROM SALES
WHERE UPDATED_NO IS NULL
AND YEAR_MONTH BETWEEN '2023-01' AND '2023-12'
GROUP BY YEAR_MONTH
ORDER BY YEAR_MONTH)),
SUB2 AS (SELECT YEAR_MONTH,
SUM(MONTH_AMT) OVER(ORDER BY YEAR_MONTH ROWS BETWEEN 11 PRECEDING AND CURRENT ROW) AS YEAR_MOVE_AMT
FROM (SELECT SUBSTRING(SALES_DATE, 1, 7) AS YEAR_MONTH,
SUM(SALES_AMT) AS MONTH_AMT
FROM SALES
WHERE UPDATED_NO IS NULL
GROUP BY YEAR_MONTH
ORDER BY YEAR_MONTH))
SELECT SUB1.YEAR_MONTH, MONTH_AMT, CUML_AMT, YEAR_MOVE_AMT
FROM SUB1
INNER JOIN SUB2
ON SUB1.YEAR_MONTH = SUB2.YEAR_MONTH