
Because the 1926 census for Northern Ireland has been destroyed, the first post-1911 census that survives for Derry City is that for 1937. Under existing legislation, this won't be released to the public until 2038, which leaves the annual editions of The Derry Almanac as the closest surviving census-type documents for the period from 1912 to 1936.
Brian has transcribed both the 1921 and 1930 Almanac using five fields: surname of head of household, first name of head of household, street address, house number, and Almanac page number of the respective listing, creating census-substitutes for the city's inhabitants for the year before Partition and again nearly one decade later.
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