Does Anthem take place in the past, the present, or the future? How do we know?

Although the novel, Anthem by Ayn Rand, was written in 1937, the novel takes place in the future.  We are not told the exact year or setting, but a Great War occurred that changed everything about the previous society.  A war between powers was mentioned, as well as “The Great Rebirth” when all knowledge and books were burned.  The lack of knowledge threw the society into a time equivalent to the Dark Ages where there was very little advancement.  Equality and his fellow brothers were taught backwards ideas in school, like the Earth is flat.  The society only had candles to see by and no books to learn from.  There were no advanced technologies or machines to help the citizens work or live comfortably. 

What Equality discovers in the tunnel under the city reveals that society once had electricity, cars, and skyscrapers. It was a different civilization that believed in individuality and human rights.  Because of the war, in which nations upholding democracy lost, the society in Anthem regressed and established its collective government that valued the group over the individual.