This paper investigates the differences between directly and indirectly seasonally adjusted aggregates. This difference is derived analytically for linear seasonal adjustment methods. GDP data for five European countries and three classes of seasonal adjustment methods are used to show...

National accounts data are always revised. Not only recent data, but also figures dating many years back can be revised substantially. This means that there is a danger that an important part of the central bank's information set is flawed for a long period of time. In this paper we present a...