Migration statistics

Written evidence submitted by Migration Watch UK (5STATS 04)

1. The Home Office data on immigration control has undergone a substantial improvement in the last two years. The data is easy to access and examine with excellent summaries of each area.

2. The Office of National Statistics (ONS) contains a large amount of data on long-term international immigration. To a new user is not clear exactly what data is available as the ONS website can be difficult to navigate. The website search function is not selective enough in the material it returns and so hinders targeted searches for material.

3. The producers of migration statistics have engaged very well with their users. They have held the Migration Statistics User Forums which have been a great success in bringing together producers and users of the statistics. The Home Office have also held their own consultation which asked for user feedback on the statistics.

4. The briefing notes that go alongside the published statistics are written in an accessible way with good summaries and with definitions clearly explained. A member of the public should be able to use them to get a better understanding of the issues.

5. A useful addition to the range of data published would be more longitudinal data on the progress of migrants through the immigration system. For example there has been recent debate about the effect of closing the Tier 1 Post-Study Work visa. This debate would have been helped if data on the number of migrants extending their stay in the UK beyond their time on this route had been known. Similarly, now that this route is closed, it is unclear whether the Home Office will be able to publish the number of migrants switching from study to work in the UK. The "Migrant Journey" analysis undertaken by the Home Office does provide a longitudinal view of migrants in the immigration system and is a very useful addition to the information available. However, as it relates to immigration flows of several years previously its use in the current debate is somewhat limited. It is understood that such a request would involve some improvement to the relevant Home Office IT systems.

6. A medium term goal for the Home Office could be to develop their systems in conjunction with e-borders so that they can report how many migrants are in the country, their nationality, the immigration category through which they entered the country and their current immigration status. This will help in understanding who the net migrants are and allow for a more evidence based immigration control policy.

7. The ONS have recently started publishing the confidence interval for the main net migration figure. However, it is the central estimate that is widely reported and we suspect there is less awareness of the uncertainty in the figure.

8. It appears that expanding the International Passenger Survey (IPS) is not a practical option due to the large number of passengers already approached to get the current sample size of international migrants. This means that e-borders is the only realistic option for reducing the uncertainty in the net migration figure.

9. The uncertainty around the net migration figure should be reduced. The net migration figure is central to the government’s policy in immigration and their success in this area will be largely judged on this figure. It is therefore far from ideal that the true net migration figure could deviate so substantially from the calculated estimate.

January 2013