1927: With the German stock market up more than 160% in the previous 17 months, central banker Hjalmar Schacht is worried about irrational exuberance. He pressures Berlin's biggest banks to issue a joint statement in which they announce that margin loans (which enable speculators to trade stocks with borrowed money) will be restricted. The next day, "Black Friday," German stocks crash 11%, helping to trigger the early onset of economic depression.

Hans-Joachim Voth, "With a Bang, Not a Whimper: Pricking Germany's 'Stockmarket Bubble' in 1927 and the Slide into Depression, working paper, Centre for History and Economics, King's College, Cambridge, UK, 2000.

1817: The Warsaw Stock Exchange opens for trading in Warsaw, Poland, handling primarily government and corporate bonds. Initially, a mere one hour of trading, from 12 noon until 1 p.m., serves to fill all the buy and sell orders.