Unemployment: The Importance of "Seasonal Adjustment"

Unemployment: The importance of "seasonal adjustment":

The U.S. economy goes through a little business cycle every year. Business activity and employment fall, and unemployment rises, sharply in the immediate aftermath of Christmas. The economy goes through a smaller lull in the summertime.

The seasonal adjustment process attempts to create data purged of these "normal," annual fluctuations. Almost all the data quoted is seasonally adjusted data.