Do like belowSELECT v.VendorName,v.VendorType,COUNT(po.PurchaseOrderID) AS TotalPOs,COUNT(CASE WHEN po.ackflag=1 THEN po.PurchaseOrderID ELSE NULL END) AS POsAccepted,COUNT(CASE WHEN po.ackflag=0 THEN po.PurchaseOrderID ELSE NULL END)AS POsPending,(COUNT(CASE WHEN po.ackflag=1 THEN po.PurchaseOrderID ELSE NULL END)+COUNT(CASE WHEN po.ackflag=0 THEN po.PurchaseOrderID ELSE NULL END))*1.0/POHosted AS Percentage Effectiveness FROM Vendors vINNER JOIN purchaseorder poon po.VendorID=v.VendorIDGROUP BY v.VendorName,v.VendorType
Also replace POHosted by actual calaculation to find it ( i dont know how to determine it as you've provided the info)