Administrative Records and Surveys as Basis for Statistics on International Labour Migration

This paper discusses possible sources for statistics to be used for describing and analysing the number, structure, situation, development and impact of migrant workers. The discussion is focused on key, intrinsic features of the different sources, important for the understanding of their strengths and weaknesses, and draws the reader's attention to features which may tend to undermine the quality of the statistics produced as well as ways in which the impact of such features can be evaluated and, if possible, reduced. This discussion thereby provides concrete illustrations of many of the methodological issues referred to in (Hoffmann, 1995). The paper is organized around three key groups of migrant workers:

• (a) Persons who are arriving in a country to work there, i.e. the inflow of foreign workers;
• (b) Persons who are leaving their country to find work abroad, i.e. the outllow of migrant workers
• (c) Stock of foreign workers in the country.

Definitions of these groups are given in section 2. Sections 3 to 5 review, for each key group, main possible sources of statistics and the extent to which they can cover the group and identify separately important sub-groups. The discussion in each section distinguishes between administrative registrations and statistical surveys, and deals with the capacity of a source to provide estimates of the size of the group, and whether it can provide estimates of the amount of change in the group over time, or at least indications of the direction of such changes. Section 6 outlines problems related to other data quality dimensions, such as frequency and timeliness of the statistics as well as the validity, reliability and consistency of the registration of variables used to describe migrant workers and where they come from. Section 7 presents strategies for the development of statistics on migrant workers based on two model scenarios for “countries” of different geographic circumstances and institutional capacities. Summary recommendations on how to organize cooperation, for the production of statistics on migrant workers, between the relevant agencies and between them and the potential users are proposed in the concluding section. The overall conclusion is that trying to piece together a coherent statistical picture of any of the above key groups is similar to trying to put together a large puzzle based on photographs of a rapidly changing reality, with important pieces missing and many of the available photographs out of focus.