The Forgotten Depression tells of the slump of 1920-21: high unemployment, collapse in commodity prices, upsurge in bankruptcies and sharp break in stock prices. However, unlike the Great Depression, the 1920 affair was over in 18 months. What explains its brevity? James Grant, publisher of the prestigious Grant’s Interest Rate Observer, tells the story of America’s last governmentally-untreated depression; relatively brief and self-correcting which gave way to the Roaring Twenties…