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entire address history of individuals who resided in San Francisco at some point between the years of 1980 and 2016.1 The data include not only individuals' San Francisco addresses, but any other address within the United States at which that individual lived during the period of 1980-2016. The dataset provides the exact street address, the month and year at which the individual lived at that particular location, the name of the individual, and some demographic information including age and gender. To examine the representativeness of the Infutor data, we link all individuals reported as living in San Francisco in 1990 to their census tract, to create census tract population counts as measured in Infutor. We make similar census tract population counts for the year 2000 and compare these San Francisco census tract population counts to those reported in the 1990 and 2000 population counts for adults 18 ,years old and old. A regression of the Infutor populations on census population are shown in Figures A.1 and AY Figure A.1 shows that for each additional person recorded in the 1990 Census, Infutor contains an additional 0.45 people, suggesting we have a 45% sample of the population. While we do not observe the universe of San Francisco residents in 1990, the data appear quite representative, as the census tract population in the 1990 Census can explain 70% of the census tract variation in population measured from Infutor. Our data is even better in the year 2000. Figure A.2 shows that we appear to have 1.2 people in Infutor for each person observed in the 2000 US census. We likely over count the number of people in each tract in Infutor since we are not conditioning on year o death in theltrfut-GrdutT.,-lyding-tu-over counting of alive people. However, the Infutor data still track population well, as the census tract population in the 2000 Census can explain 90% of the census tract variation in population measured from Infutor. Now, Infutor matches well the level of the San Francisco population and generates an even higher R2 of 89.9%. We merge these data with public records information provided by DataQuick about the 4Infutor is a data aggregator of address data using many sources including sources such as phonebooks, magazine subscriptions, and credit header files. 'We only can do data validation relative to the US Censuses for census tracts in San Francisco because we only have address histories for people that lived in San Francisco at some point in their life. I