Question
Why are the results of National Accounts revised?
Answer
The early first release of GDP data meets the user need for up-to-date results although frequently the data basis is not yet complete at that point in time. The first provisional figures are revised several times in order to include statistical information that has become available in the meantime; they may deviate from the final results, which are released after about four years.
Also, large-scale revisions are performed, whose purpose is among other things to introduce new concepts and definitions, to change over to a new price base or to include the results of new surveys or censuses or those conducted at irregular intervals.
In a multi-annual comparison, the first provisional results may be above or below the final value by about half a percentage point. For some GDP sub-aggregates, the average need for revision is considerably larger.
