Importance of Official Census Dates
It is important to use the official census dates when incorporating census information into genealogy records. Each census year is assigned an official date by the census agency. Enumerators are instructed to ask that answers to their questions be "as of" that official date, notwithstanding the actual date a particular enumerator may have visited a particular household, and whether or not that date was recorded on the schedule. Because it is impossible to know if enumerators and attestors adhered to those "as of" instructions, assuming the official date was adhered to assures consistency in genealogy records when calculating event dates from census information.