SELECT TOP 5 C.LastName, 
             C.FirstName, 
             E.BusinessEntityID, 
             SUM(SOH.SubTotal) AS SaleAmount

FROM       Sales.SalesPerson             SP 
INNER JOIN HumanResources.Employee       E   ON SP.BusinessEntityID    = E.BusinessEntityID 
INNER JOIN Person.Person                 C   ON E.BusinessEntityID     = C.BusinessEntityID 
INNER JOIN Sales.SalesOrderHeader        SOH ON SP.BusinessEntityID    = SOH.SalesPersonID 
INNER JOIN Sales.SalesOrderDetail        SOD ON SOH.SalesOrderID       = SOD.SalesOrderID 
INNER JOIN Production.Product            P   ON SOD.ProductID          = P.ProductID 
INNER JOIN Production.ProductSubcategory PS  ON P.ProductSubcategoryID = PS.ProductSubcategoryID 
INNER JOIN Production.ProductCategory    PC  ON PS.ProductCategoryID   = PC.ProductCategoryID

-- Following WHERE clause is in original MSFT download
--WHERE       (PC.ProductCategoryID = @ProductCategory)          AND 
--            (PS.ProductSubcategoryID IN (@ProductSubcategory)) AND 
--            (SOH.OrderDate > @StartDate)                       AND 
--            (SOH.OrderDate < @EndDate)

-- Revised WHERE clause, use BETWEEN for date range
WHERE       (PC.ProductCategoryID = @ProductCategory)          AND 
            (PS.ProductSubcategoryID IN (@ProductSubcategory)) AND 
            (SOH.OrderDate BETWEEN @StartDate AND @EndDate)

GROUP BY    C.LastName, 
            C.FirstName, 
            E.BusinessEntityID, 
            PC.ProductCategoryID,
            PS.ProductSubcategoryID

ORDER BY   SUM(SOH.SubTotal) DESC