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In a single-stage sample where the units report on multiple occasions, it is typical for some units to drop out of the sampling frame over time (the deaths); for new units to be added to the frame (the births); while the remaining units stay in the original frame and, if selected, in sample. In this paper we discuss an approach to adding sample units from the frame of continuing and birth units to compensate for the deaths, and reweighting the modified sample so that it results in unbiased estimates in the sense that the expected weight of each unit in the modified frame over all possible samples is 1. A possible application to sample augmentation for the first-stage sample of the Producer Price Index, conducted by the Bureau of Labor Statistics, is discussed, as are alternative sampling procedures that focus on partially converting the augmented sampling process to the selection of a single PPS sample.