the instituto brasileiro de geografia e estatística - ibge (brazilian institute for geography and statistics) is one of the most important government organizations that focuses of geography and statistical analysis by region - the website make available a wealth of data on population, economy, and geosciences.

the website covers the entire country and data pertaining to rio de janeiro is found within the sub-menus by municipality.  the ibge also makes available all census data for 2010 on this link.

this page by the fundação Getúlio vargas, based on data from pnad/ibge, is an 'income simulator' that allows researches to estimate income for rio's residents by selecting several parameters including gender, age, race, education, type of work, and domestic inter-state immigration status.