Você pode usar
SUM com ORDER BY cláusula dentro do OVER cláusula:SELECT Account, Month, Salary,
SUM(Salary) OVER (PARTITION BY Account ORDER BY Month) AS RunningTotal
FROM mytable
SUM com ORDER BY cláusula dentro do OVER cláusula:SELECT Account, Month, Salary,
SUM(Salary) OVER (PARTITION BY Account ORDER BY Month) AS RunningTotal
FROM mytable