error in query

getting error while finding 7dayrolling_avg in 1 case study when using group by SELECT ds, (COUNT(job_id) OVER (ORDER BY ds ROWS BETWEEN 6 PRECEDING AND CURRENT ROW)/ SUM(time_spent) OVER (ORDER BY ds ROWS BETWEEN 6 PRECEDING AND CURRENT ROW)) AS 7dayrolling_avg FROM job_data group by ds;