How did shifting government policy contribute to both of the 1920s bust of 1929

On Thursday October 24th 1929 the great New York stock exchange panic began. 12,894,650 shares changed hands, many at fire sale prices. The following Black Tuesday October 29th Wall Street began its long meltdown. The Wall Street crash divides two eras: the jaunty 'jazz age' of the 1920s and the 1930s - the decade of depression.