By Dominic Casciani
BBC News home affairs reporter
New figures from the Office of National Statistics show, among other things, net immigration to the UK increased by 46,000 last year.
But what do these latest figures mean? And what do they tell us about the future population?
The headlines are clear - the population is rising largely down to increased immigration - but the details reveals a complex picture of people coming and going.
THE BIG PICTURE
The latest figures from the Office for National Statistics show that a long-term trend of more people coming to live in the UK than leaving to live elsewhere has continued.
What this means is that the UK population rose by almost a quarter of a million in 2007 - the second highest recorded annual increase after 2004:
However, the detail shows the reality of migration is quite complex. The number of people who came to live in the UK fell from 591,000 in 2006 to 571,000 in 2007.
But the number of people who left the UK fell further - from 400,000 émigrés to 340,000. The numbers include foreign and British nationals moving in both directions - although eight out of 10 of those arriving were not UK passport holders.
This second graph shows the difference between people coming and going - and how a fall in one affects the net effect of the other:
WHO IS COMING TO THE UK?
This is the element that has seen the most dramatic changes since 2004 with the opening of our jobs market to Eastern European nations when they joined the EU.
The largest single group of people who came to the UK were from within the European Union - a net arrival of 128,000. The graph below shows figures for the old "EU15" member states, the eight Eastern nations who joined in 2004 and all current 27 members together.
The EU nationals are people who are taking advantage of the free labour market, a right open to British citizens too. The next largest groups are "new commonwealth" - the former British colonies - and people from other parts of the world. The "old commonwealth" - Canada, Australia, South Africa and New Zealand, are a very small part of migration.
Migration is not a one-way street. There is also substantial emigration from the UK. For almost 20 years from the early 1960s the UK was losing more people abroad than it was gaining from immigration - many of whom answered a call to start a new life in Australia. British people still leave - and the favoured destinations remain English-speaking destinations, plus Spain and France. But the numbers have now dropped:
The reasons for the fall in emigration are unclear - but speculation centres on the global economy. British people bought a lot of property abroad in recent years benefiting from a strong pound and their ability to borrow against rising house prices at home. Those circumstances have significantly changed in the past year.
REASONS FOR MIGRATION
The statistics show a difference in the reasons behind why people come to the UK - and why they leave. The largest number of people who are moving in any direction are naturally doing so for work reasons. The numbers joining another member of the family in the UK or abroad is virtually identical in each group of figures. But the big difference is study:
Very few Britons go abroad to study - but large numbers come to the UK - a quarter of all immigrants in 2007. The British universities have expanded massively in recent years to take in foreign students because they pay full course fees, playing an important role in the economics of higher education.
SIGNS OF CHANGES
The political debate around immigration has recently shifted focus to the idea of attempting to cap numbers, amid official projections which suggest the population could reach 70m by 2031. This is a hotly disputed figure - with ministers saying it is being quoted out of context. One of the key areas being watched is the number of workers from Eastern Europe who are registering:
The figures in the graph above show that the rate of registrations has now dropped for four quarters in a row. Coupled with the main migration figure showing a drop, some experts say this means the trend is already showing a move away from the 70m projection as global economic circumstances change.
National Insurance number requests, another key measure, have also fallen in the first half of 2008.
Separate research suggests that most Eastern European workers, who are relatively young, don't intend to stay for the long-term in the UK.
There's been a slight fall in the number of Eastern European workers bringing dependents to the UK - but it is perhaps too early to draw any conclusions from that alone.
WHO STAYS FOR THE LONG-TERM?
The main measure of which immigrants seek to stay on is the count of people who ask for a "grant of settlement". A successful applicant is legally resident in the UK and no longer subject to immigration control - but it is a status that falls short of being a British citizen. The latest figures show that grants have slowed in the last two quarters:
The two principle categories for grants are employment - where someone has a long-term wish to stay in the UK because of their work - and family reasons, such as marriage or reunion.
Citizenship applications have correspondingly dropped in the last two quarters after a record high in 2007 shortly before the introduction of new charges.