By late 1923 it took 4.2 trillion German marks to buy one US dollar

Germany financed WWI and its postwar reparations partly by printing money, and paper marks in circulation exploded from about 1.3 trillion at the end of 1922 to nearly 500 quintillion by November 1923. Workers were paid twice a day and raced to spend wages before prices rose again within hours. A new currency, the Rentenmark, backed by mortgaged land rather than gold, finally stopped the collapse in November 1923.

— Adam Fergusson, When Money Dies: The Nightmare of the Weimar Hyper-Inflation — 1975, revised edition 2010
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