LISTING 3: Solution 1, Second Step: View That 
Returns Each Month’s Trend and a Differentiating Factor

CREATE VIEW VTrendsDiff
AS

SELECT *,
  (SELECT COUNT(*)
   FROM VTrends AS VT2
   WHERE VT2.smonth >= VT1.smonth
     AND VT2.trend <> VT1.trend) AS diff
FROM VTrends AS VT1
GO