Newly available geographical information from the Panel Study of Income Dynamics (PSID) is used to estimate a variety of relationships involving high-poverty metropolitan census tracts. The longitudinal data from the PSID show a great deal of geographical mobility even for persistently poor adults, with as many as one fourth of certain groups of these entering and leaving poor urban census tracts in a year. At the same time, solution of the transition matrices for various groups-whites and blacks of various income classes, in families with and without children, living in different types of census tracts-in the early 1980s shows the gradual emptying out of poor urban tracts, particularly of whites and blacks in families without children. As a consequence, despite the great degree of geographical "churning," poor urban areas gradually become poorer, blacker, and the home of a larger share of black families with children. Some of these aggregate trends had been noticed by researchers comparing these areas in the 1970 and 1980 censuses; our more up-to-date results demonstrate the relationships between the micro and macro data.
