Comparability

Comparability - geographical

The calculation of the Household Budget Survey is based on international recommendations and therefore there is a good correlation with figures from countries of the European Union. Eurostat publishes every five years each country's Household Budget Survey in their publication databases.

Comparability over time

The first time Danes' consumption was recorded was in 1897, when the consumption of Danish working families was investigated. Up until 1994, various studies were carried out on Danes' consumption - and for different groups of the population. Thus, in 1909, household accounts were made for each urban workers, farm workers, householders and farm workers and in 1916 for civil servants' families. From 1971 consumption surveys have been carried out. In 1971, it was the consumption of wage earners that was investigated and from 1976 it is the consumption of private households that is investigated.

Since 1994, annual surveys of Danish households' private consumption have been carried out. The collection method has been to collect data for three consecutive years, which were combined to form a sample. Data from year t -1 and t +1 have been price and quantity adjusted to year t (mid-year) level. The disadvantage of the model has been that it only replaced data for year t +1 and price and quantity converted to the middle year, t. The study has therefore had the character of a kind of moving average. Basing the sample on a 2-year sample from 2014 did not solve the problem. However, it accelerated the production of data and thus made the study more timely and relevant. The method continues to be annual data collections. The sample now consists of years t -1 and t. The sample for 2022 thus consists of data from the year 2021 (t-1) and the year 2022 (t). These prices and quantities are converted to the price level in 2022.

Since the publication of figures for 2014, the Household Budget Survey has been based on a 2-year sample and follows the ECOICOP nomenclature. The consequence of these changes is that revised data from the publication of figures for a given year. t is now published 12 months after the reference year, compared to 22 months previously. To ensure comparability and continuity, data from 1994 until 2012 has been recalculated according to the ECOICOP nomenclature in both current and fixed prices.

Since 2012, the survey has been supplemented with data in constant 2005 prices. This makes it possible to determine the volume development over time.

Coherence - cross domain

The classifications and definitions used are aimed to be as comparable as possible with the national accounts. But the methods, etc., in these two kinds of statistics are very different. The classification of consumption is based on the international COICOP5 classification, which is also used in compiling price indices. It is difficult to conduct comparisons with the general population statistics and other register-based statistics, as the household definition in the survey is different: In the survey the household definition is the economic unit, which is decided by the household members themselves, while in the general population statistics the household definitions are derived from the administrative registers-based information.

Coherence - internal

The Household Budget Survey is based on three data sources, interviews, accounting and registers. A great deal of work is done to ensure that the register information used is consistent and valid in relation to linking it to the interview and the accounting information.