Accuracy and reliability

Overall accuracy

Setting up the account system involves a number of consistency checks, data confrontations and checks by comparison with financial accounts. Data originates from so many different sources that it is difficult in practice to come up with a figure for the uncertainty. However, the difference between the borrowing or lending, net, calculated from the financial side of the national accounts and the borrowing or lending, net, calculated from the non-financial part of the national accounts can be considered to reflect the overall uncertainty in the financial as well as the non-financial part of the national accounts.

Sampling error

Not relevant for these statistics.

Non-sampling error

It is possible to assess some parts of the national accounts more accurately than other parts, because better source data is available in these areas. For example, there is quite accurate data for the manufacturing industry in general, whereas there is less accurate data for Danish-based enterprises that predominantly purchase and sell products abroad. Finally, there are also areas for which there is no source data, such as use of owner-occupied dwellings and moonlighting. In these areas, the national accounts rely almost entirely on calculations and estimates, which is why the uncertainty here can be more significant.

Another circumstance affecting the accuracy and reliability of the national accounts is the fact that errors may be corrected in the national accounts’ many source statistics after the final version of the national accounts has been prepared. At that point, these corrections cannot be included in the national accounts until the next major revision with an interval of years, where long-term series of final years can be corrected. This contributes to increase the uncertainty of the national accounts.

In the long term, the accuracy and reliability of the national accounts is restored, however, because corrections in the source statistics are included in the major revisions.

Lately there has been a tendency to make upward adjustments of the investments. This means that a somewhat higher uncertainty must be expected for the calculation of the investments than for other variables. The uncertainty for the investments is described in the memo Need for improved estimates of investments.

The real growth in public production and public consumption is also subject to particular uncertainty, since the real growth is mainly based on volume indicators that are undergoing continuous development and quality assurance in terms of both data basis and method.

Globalisation implies that Danish enterprises are increasingly organising their production with an international set-up, and this has an impact on the Danish national accounts and Danish GDP. See e.g. Statistics Denmark’s analyses:

• Production abroad has an effect on Danish GDP
• The global set-up of industrial groups impacts the statistics on Danish production and income.

Consistency processing and detailed incorporation of data on the large groups of companies is resource demanding. For this reason, there is higher uncertainty for the early versions of external trade and balance of payments, and all other things being equal, this also results in revisions of the national accounts.

Quality management

Statistics Denmark follows the recommendations on organisation and management of quality given in the Code of Practice for European Statistics (CoP) and the implementation guidelines given in the Quality Assurance Framework of the European Statistical System (QAF). A Working Group on Quality and a central quality assurance function have been established to continuously carry through control of products and processes.

Quality assurance

Statistics Denmark follows the principles in the Code of Practice for European Statistics (CoP) and uses the Quality Assurance Framework of the European Statistical System (QAF) for the implementation of the principles. This involves continuous decentralized and central control of products and processes based on documentation following international standards. The central quality assurance function reports to the Working Group on Quality. Reports include suggestions for improvement that are assessed, decided and subsequently implemented.

Quality assessment

The ESA 2010 regulation requires that Eurostat assess the quality of data reported under the ESA transmission program. This is done on the basis of the countries' quality reports which are not published independently by Eurostat. The report is prepared annually. Read the quality assessment of Denmark's national accounts in:

Quality Report, Denmark 2020 - National Accounts.

Data revision - policy

Statistics Denmark revises published figures in accordance with the Revision Policy for Statistics Denmark. The common procedures and principles of the Revision Policy are for some statistics supplemented by a specific revision practice.

Data revision practice

Preliminary annual non-financial sector accounts are prepared and published twice a year: end of March and end of June. Final national accounts are published once a year at the end of June three years after the reference year.

Major revisions are made at five years’ interval, where long-term series of final national accounting years are corrected. Because of this, the accuracy and reliability of the national accounts is improved, because main revisions take all corrections in the source statistics and processing errors into account. The next major revision will be published June 28th 2024.

Since the main purpose of the non-financial sector accounts is to provide a basis for an overall assessment of the economy’s structural and cyclical trend, great emphasis is placed on the continuity in time series, and for that reason, level errors are usually not corrected until the next major revision.

The non-financial sector accounts for a given quarter are prepared in a series of preliminary versions. The quarterly national accounts and the non-financial sector accounts are consistent with the latest final annual national accounts, which is available approximately three years after the census year. A plan for the scope of quarters being calculated and revised in the individual statistical recordings is available at https://www.dst.dk/nationalregnskab. The working papers for the current annual versions of the national accounts are also available there..