Weimar Republic (German: "Weimarer Republik" ] ) was an unofficial, historical designation for the German state between 1919 and 1933. The name derives from the city of Weimar, where its constitutional assembly first took place. The official name of the state was "Deutsches Reich"; it had remained unchanged since 1871. In English the country was usually known simply as Germany.

Can we draw the following conclusion?
Weimar Republic was an unofficial, historical designation for the German state for less than 20 years

Select from:
a). Yes
b). It's impossible to say
c). No
a).