I’m a data librarian helping a graduate student who is working with tract-level summary data from NHGIS from the 1920 census for Kings County (Brooklyn) New York. The tract shapefile from 1920 contains 965 tracts for the county. Of these tracts, 357 are coded with a nodata value in the GISJOIN field, while the other 608 have regular identifiers. When I look at a data table like 1920_tpop_nyc it has records for 585 tracts. Essentially there are a large number of tracts for which no data exists.
My question is - if tract boundaries were delineated for the entire county, why isn’t data tabulated for all of them?
I know that the Census Bureau didn’t introduce tracts as an official geography until 1940. From 1910 to 1930 a number of social scientists drew tract boundaries and tabulated data for them on an unofficial basis for a handful of cities. My assumption is that they simply didn’t finish tabulating data for all these tracts, or the data was lost. I am hoping someone could confirm my assumption, and ideally point me to some documentation that either supports this or provides another explanation.