IF OBJECT_ID('dbo.SalesSummary') IS NOT NULL
  DROP TABLE dbo.SalesSummary;
GO

CREATE TABLE dbo.SalesSummary
(  SalesYear int NOT NULL PRIMARY KEY,
  Qty       int NOT NULL,
  Value     int NOT NULL,
  PrevQty   int NULL,
  PrevValue int NULL  );

INSERT INTO dbo.SalesSummary(SalesYear, Qty, Value)
  SELECT YEAR(OrderDate), SUM(OrderQty),
    SUM(OrderQty * UnitPrice * UnitPriceDiscount)
  FROM Sales.SalesOrderHeader AS H
    JOIN Sales.SalesOrderDetail AS D
      ON D.SalesOrderID = H.SalesOrderID
  GROUP BY YEAR(OrderDate);