Documents 2020/23

Technical documentation of the BEFINN model, g2020

This document details the workflow and technical solutions in the BEFINN model, which constitutes Statistics Norway's main model for national population projections.

Statistics Norway produces national population projections biennially. Work on model development, as well as substantive research relating to model assumptions, is undertaken in the intervening years.

The purpose of this documentation is to describe the maintenance and practical applications of the BEFINN model. In addition to the work implemented in this model, extensive external work is required in order to produce assumptions for fertility, mortality and international migration – with resulting files used as input in the BEFINN model. The external work is documented in the main report accompanying the g2020 national population projections and is therefore not discussed in this document.

A schematic overview of the model, including the programs and the input and output files, is included in Appendix A. Appendix B comprises a “cook book” detailing the order in which the various programs needs to be run. These brief descriptive summaries should be regularly consulted during the production of a new national population projection.

About the publication


Technical documentation of the BEFINN model, g2020


Michael Thomas, Rebecca Gleditsch and Astri Syse

Series and number

Documents 2020/23


Statistics Norway


Methods and documentation

ISBN (online)




Number of pages


About Documents

Documentation, descriptions of methods, models and standards are published in the series Documents.