You asked

I'm wondering if there is any available data regarding principal population projections for the 1979-based and 1994-based projection series, with population numbers by sex and single year of age.

I understand they were carried out by the Government Actuary's Department (GAD) back then. Totally understand if data is difficult or impossible to find from so far back.

We said

Thank you for your Freedom of Information request about data regarding principal projections for the 1979-based and 1994-based projection series, with population numbers by sex and single year of age.

As you mentioned, data for this period were produced by the Government Actuaries Department with responsibility for them later passing to ONS. We have attached tables for 1979-based and 1994-based projections at UK level. While they do give separate projections for female and male, they are by age groups and not single year of age.

The latest principal population projections are 2018-based, as are the subnational population projections.

When accessing any of our files please read the 'notes, terms and conditions' contained within them.

Please do not hesitate to contact us directly on pop.info@ons.gov.uk if you require anything further.