Realgrößen und Preisindizes im alten und im neuen VGR-System[Macro-economic aggregates in real terms and price indices in the old and the new system of national accounts]

In 2005, Germany’s system of national accounts was altered from so called fixed prices (prices of a fixed year, in the end 1995) to prices of the preceding year as basis for calculating macroeconomic time series in real terms. Compared to the previous SNA, the new system offers a wider range of possibilities to interpret theoretically relevant variables empirically. There are, for instance, at least three possibilities to express the main aggregates of an economy in real terms. At least two of them are no longer additive in respect to the sub-aggregates they comprise. But this is not the only problem: Quarterly data of macro-economic variables are calculated by using the annual overlap method which cannot always easily handled by such a standard program for time-series analysis like E-Views. Both problems raised serious concerns about the applicability of econometric models to the new data basis. The focus of the paper is laid on the basic features of the new possibilities to express macro-economic aggregates in real terms. It turns out that the non-additivity of some variables is not a problem as far as non-additive chained time series can be altered to additive non-chained time series and vice versa.