ECINF, the Urban Informal Economy survey, is a sample survey that was conducted by IBGE in 1997 and 2003 to investigate the informal sector in Brazil, characterized by self-employed workers and employers running a business with up to five employees. The main interest of this survey are businesses' characteristics, such as operating location (whether it operates in a store, in a motorized vehicle etc.), type of clientele, investments made in the previous year, age of the business, etc. In 2003, ECINF's sample covered 54,595 households, with a total of 195,504 individuals.