[The evolution of employment in agriculture]

Data collected from population and agricultural censuses concerning agricultural employment in Brazil are compared. "This study aims at analyzing the origin, the form and the significance of the differences between the two censuses. In this first part a detailed comparison is made between their respective concepts, their methodologies, their limitations and their outcomes. The comparison goes back even to the first modern censuses in order to evaluate the evolution of censal instruments and its importance for the...understanding of employment in agriculture." Other data sources are also considered. (SUMMARY IN ENG)