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French Equivalent: Correction des variations saisonnières

Seasonal adjustment is a statistical technique to remove the effects of seasonal calendar influences operating on a series. Seasonal effects usually reflect the influence of the seasons themselves either directly or through production series related to them, or social conventions.

Other types of calendar variation occur as a result of influences such as number of days in the calendar period, the accounting or recording practices adopted or the incidence of moving holidays (such as Easter).

Series are adjusted for seasonal variations and in some cases for calendar working days variations.

Seasonal adjustment is normally done using off-the-shelf programs -most commonly worldwide by one of the programs in the X-11 family. Other programs in common use include the TRAMO-SEATS package developed by Bank of Spain and promoted by Eurostat and the German BV4 program (International Monetary Fund (IMF)," Quarterly National Accounts Manual", Washington D.C., 2001, para. 8.13).

Under the SDDS this entails the availability, publication, and level at which seasonal adjustment takes place, the methods used and an indication regarding which data series the methods are applied to (e.g. aggregate series derived from lower-level seasonally-adjusted series versus independently adjusted; adjusted at 1-digit SITC level using X-11 method and aggregated to totals; seasonal adjustment is conducted on four components of final expenditures (after annual balancing) and then aggregated to total GDP), and on consumer and producer price indexes.

Source Publication:
Australian Bureau of Statistics, "An Analytical Framework for Price Indexes in Australia: Glossary and References", Canberra, 1997.

Cross References:
Compilation practices
Not seasonally adjusted
Seasonal adjustment programs
Special Data Dissemination Standard (SDDS)
Trend estimates


Statistical Theme: Methodological information (metadata)

Glossary Output Segments:

Created on Tuesday, September 25, 2001

Last updated on Tuesday, January 3, 2006