The Impact Of Immigration On Population Growth

New calculations by Migration Watch UK in a paper published today show that net migration has accounted for about 84% of the UK’s population increase over the past decade.

    The official publications of the Office for National Statistics (ONS) state that, on average, 57 per cent of UK population increase since 2001 has been due to net migration with the remainder resulting from the excess of births over deaths – the “natural increase”.  On the face of it, this is correct.

    However, the ONS figure substantially understates the demographic power of migration. Much of that natural increase came from immigrant parents.   Thus, if a couple arrived last year and then had a family, their children would not be counted as part of the immigrant contribution to population growth although they clearly are.  (This calculation is, of course, about numbers, not citizenship or identity).

    Migration Watch has now calculated this immigrant contribution to natural increase which, when included, brings the total contribution of migration to UK population growth over the period from 2001 to 2012 to between 83% and 85%.   Thus, of the 4.7 million population increase in the period, 3.9 million was due to immigration.

  For similar reasons to those outlined above, the ONS estimate of 60% of future population growth to 2037 being due to migration must be a serious under-statement, given that the migration contribution is already about 84%. Unless there are unexpected changes we would expect that, if current levels of immigration were to continue, the percentage of our future population increase due to migration would increase steadily from the 84% we have calculated for the past 12 years.

     Looking further into the future, it is relevant that the UK fertility rate has been below 2.1 for 40 years. The present level is 1.83.  If it remains at that level (which it may not) then in the long term (say 25 years or so) any population increase would be entirely due to net migration. That is indicated by a comparison of ONS projections with and without migration. However, even with zero net migration, our population would continue to increase for the next 25 years or so.

    It is worth noting that this massive impact of net migration on the growth of the UK population is a relatively recent development.  Annual net migration between 1991 and 1997 averaged about 45,000 but increased dramatically from 1998.  As a result, annual net migration has now averaged nearly a quarter of a million a year for the past ten years.  That, together with the natural increase from immigrants living in the UK is now the chief driver of UK population growth.

    Commenting, Sir Andrew Green, Chairman of Migration Watch UK, said, “This is about population growth, not about citizenship.  Those born in the UK to settled immigrant parents are British citizens, irrespective of their parents’ country of birth.  That said, it is now undeniable that the massive scale of net migration has been the main cause of our population growth and that, in the future, our population growth is likely to be almost entirely due to migration. The conventional official statistics published in the ONS official statistics do not make this clear.

    “The reality is that even if net migration is bought down to 165,000 a year, we will, in the next 25 years, have to build the equivalent of ten cities the size of Birmingham – amounting to almost twice the population of Scotland. This would place enormous stress on our already creaking infrastructure and on our environment and it would also change the nature of British society for ever. We must not sleep walk into one of the most significant changes in a thousand years of our island’s history”.