SELECT Month, ROUND(Sales,0)/1000 AS M_Sales, 
            ROUND(AVG(Sales) 
                OVER (ORDER BY Month ROWS 2 PRECEDING),0)/1000 
                            AS Moving_3_M_Avg_Sales
FROM (
            SELECT monthnumberofyear Month,  
                        ROUND(SUM(transactionprice*quantity),0) AS Sales 
            FROM factonlinesales fos INNER JOIN dimdate dd
                ON fos.orderdatekey= dd.datekey
            WHERE  calendaryear = 2024
            GROUP BY monthnumberofyear
            )
ORDER BY 1, 2 ;