The infra-annual dataflow on working age population is a subset of the infra-annual labour statistics database, which contains predominantly monthly and quarterly statistics on the working age population by age groups (15+, 15-24, 25-54, 55-64, 15-64 and 15-74 where available) and sex and associated statistical methodological information, for the OECD member countries and selected other economies.

The working-age population is commonly defined as persons aged 15 years and older.

The infra-annual labour statistics compiled for all OECD member countries, are drawn from Labour Force Surveys based on definition provided by the 19th Conference of Labour Statisticians in 2013. The uniform application of these definitions across all OECD member countries results in estimates that are internationally comparable.