If you are thinking about a career in teaching, the message is clear: train as a primary teacher.

With the number of under-fours in England rising until the early 2020s and the number of five to nine-year-olds on the rise until 2027 - according to Government projections - the opportunities for teachers in this sector could be much greater than for their secondary school compatriots.

The number of 10 to 14-year-olds in England was already in decline in 2010, and will continue to fall until 2013. At that point it will begin to rise, but it will not be enough to compensate for the fact that the number of 15 to 19-year-olds is falling until 2019, at which point the secondary sector starts growing again.

There are similar patterns of population change in the devolved nations of Wales, Scotland and Northern Ireland.

Within England, the changes are not uniform. Regionally, the largest areas of growth in the number of younger pupils between 2009 and 2015 are London, Yorkshire, the East Midlands and the East of England. The lowest growth is in the North East, Northern Ireland, Wales and Scotland.

London is the only region where the 10-14 age group is expected to increase between 2009 and 2015. Everywhere else this group reduces in number over the next six years, with the largest declines being in Scotland, Wales, North East England and Northern Ireland.

Attracting teachers to London will be a key concern for at least the next two governments, whereas any teacher moving to Scotland is likely to find job hunting tough for most of the next decade.

John Howson is director of Education Data Surveys, part of TSL Education.