The U.S. Census Bureau identified a problem with tract numbers within the block group summary level in the 1990 Decennial SF1 API endpoint. The tract listed with the block group was sometimes incorrect. This resulted in some data being placed in the incorrect tract within the block. The U.S. Census Bureau has removed all of the block group data that was available for this endpoint. Data for tracts were processed correctly. We hope to correct this error and publish the API with block groups in the future.
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