Description of methods and sources for Albania - INSTAT

IPA 2009 Multi-beneficiary StatisticalCooperation ProgrammeThe direct approach will often give better results if the component series showsimilar seasonal patterns. At the most detailed level, the irregular factor may belargely compared with the seasonal factor and therefore may make it difficult toperform a proper seasonal adjustment. In a small country such as Albania, irregularevents can have a strong impact on particular data. However, if the component seriesshow the same seasonal pattern, aggregation often reduces the impact of the irregularfactors in the component series. This is particularly relevant for Albania, where manyeconomic series are affected by seasonal fluctuations in the primary industries.“INSTAT” institute has decided to apply the direct seasonal adjustment method,because in countries like Albania it is better to work based on an aggregate level.This happens because the economy is changing at a rapid pace.To eliminate the seasonality effect, specific software “Demetra” is used, which isbased on some statistical tests like X 12 ARIMA, Tramo – seats, etc.A numerical example is given in Annex I, Tab I.2.18.2.4 Chain linking techniqueQuarterly accounts have to be both time consistent with the annual accounts (forexample the sum of quarterly values of the GDP must be equal to the annual value ofGDP) and respect the accounting identities (for example, the sum of quarterly valuesof the GDP expenditure components should be equal to the corresponding quarterlyvalue of GDP).Time consistency is a fundamentally univariate problem since it involves only onevariable, albeit at two frequencies (annual and quarterly). Accounting coherence andtime consistency combined exhibit a multivariate dimension, since they involveseveral variables linked by a contemporaneous constraint (in the case above, this isquarterly GDP which "constrains" the sum of the quarterly component values), witheach of the variables subject to their own univariate temporal constraint.In the Albanian case, at the detailed level the series are consistent in current pricesand in the base year prices. INSTAT presented differently the annual nationalaccounts and quarterly national accounts volume measures, creating some confusionsfor non-experienced users. Therefore one major improvement was developing amethodology for a chain volume series of QNA and to present the quarterly accountsin the previous year’s prices in order to be consistent with the annual accounts.When annual re-weighting is done two successive years have to be linked by usingone of the following techniques:annual overlap: the average annual prices of the previous year are used as weightsfor each of the quarters in the current year, with the linking factors being derivedfrom the annual data;166/236