Lei do Sistema Estadístico Nacional n. 6/89 de 15/04/1989. Diário da República I Série n. 88 de 15/04/1989 Página 1650

This law establishes the legal framework for the National Statistical System in Portugal. It defines how official statistics are collected and processed to ensure the quality, objectivity, and reliability of data used for public policy and national planning. This legislation affects government agencies, statistical offices, and entities required to provide data for official statistics, ensuring standardized data collection across the country.