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Estimates of participation in education, training and employment in England for those of academic age1 16-18 are published annually by the Department in a Statistical First Release (SFR) each June at:
http://www.dcsf.gov.uk/rsgateway/DB/SFR/s000792/index.shtml
The Department publishes local authority estimates of participation in England as additional tables alongside the national figures, including those for Plymouth local authority. The estimates cannot be further broken down by parliamentary constituency area.
1 Academic age represents the age at the start of the academic year, 31 August.