Select A.CompanyName, Year(D.OrderDate), MONTH(D.OrderDate),Sum(C.UnitPrice * C.Quantity * (1-C.Discount)) as 'Przychod'
From Suppliers as A
	INNER JOIN Products as B
		ON A.SupplierID = B.SupplierID
	INNER JOIN [Order Details] as C
		ON B.ProductID = C.ProductID
	INNER JOIN ORDERS as D
		ON D.OrderID = C.OrderID
GROUP BY A.CompanyName, Year(D.OrderDate) ,MONTH(D.OrderDate)
HAVING Sum(C.UnitPrice * C.Quantity * (1-C.Discount)) > (
		SELECT SUM(E.UnitPrice * E.Quantity * (1-E.Discount)) / (Select Count(A1.CompanyName)
																 From Suppliers as A1
																	INNER JOIN Products as B1
																		ON A1.SupplierID = B1.SupplierID
																	INNER JOIN [Order Details] as C1
																		ON B1.ProductID = C1.ProductID
																	INNER JOIN ORDERS as D1
																		ON D1.OrderID = C1.OrderID
																	WHERE
																	Year(D.OrderDate) = YEAR(D1.OrderDate)
																	AND MONTH(D.OrderDate) = MONTH(D1.OrderDate)
																	)
		FROM [Order Details] as E
			INNER JOIN Orders as F
				ON F.OrderID = E.OrderID
		WHERE
			MONTH(F.OrderDate) = MONTH(D.OrderDate)
			AND YEAR(F.OrderDate) = YEAR(D.OrderDate)
			)