Central Bank Balance Sheets: Expansion and Reduction since 1900

In this paper we study the evolution of central banks’ balance sheets in 12 advanced economies since 1900. We find that balance sheet size in most developed countries has fluctuated within rather clearly defined bands relative to output. Historically, clusters of big expansions and contractions of balance sheets have been associated with periods of geopolitical or financial crisis. Relative to the size of the financial sector, central bank balance sheets had shrunk dramatically in the three decades preceding the global financial crisis. By that yardstick, their recent expansion partly marks a return to earlier levels.