edit: I just read this somewhere: "But a word of caution. Buildings built before 1900 are often labeled 1899 or 1900 in city databases." So there may be two separate issues at play here.
DeLancey built the current building as a house in 1719. The small yellow bricks used in its construction were imported from the Dutch Republic and the sizable mansion ranked highly in the province for its quality.[7] His heirs sold the building in 1762 to Samuel Fraunces who converted the home into the popular tavern, first named the Queen's Head.
I know in the PLUTO data a lot of the entries have a year build and a number of years renovated. Even then though it appears that the year built is being used throughout the map. Probably requires an inspection of the actual row in the PLUTO data containing Fraunces Tavern.
http://en.wikipedia.org/wiki/Old_Quaker_Meeting_House_%28Flu...