NBER Working Paper, February 2000.In the paper Blanchard argues that the history of macroeconomics during the 20th century can be divided in three epochs:
Pre 1940. A period where macroeconomics was not macroeconomics yet, but moneraty theory on one side, business cycle theory on the other.
From 1940 to 1980. A period of consolidation: an integrated framework was developed, starting with IS-LM all the way to dynamic general equilibrium models.
From 1980. Period focused on imperfections in macroeconomics (the relevance of nominal price setting, incompleteness of markets, asymmetry of information, decentralized markets etc.)
