There was an error in the formula to calculate the valus of AW ceiling, Which step OW ceiling minus AW ceiling to find the final AW limit for calculate CPFAW in the period or not. This formula which is specifly the wrong point as below
AW Limit for calculate CPFAW = OW ceiling - (AW ceiling)
In this case the AW ceiling has a negative value, after calculation AW ceiling the system will return the positive value into AW limit, because of this case system will result in miscorrect