51: January 6, 1931 - April 28, 1931  52: April 29, 1931 - July 1, 1931  53: July 2, 1931 - October 12, 1931  54: October 13, 1931 - February 8, 1932  55: February 10, 1932 - June 15, 1932  56: June 16, 1932 - September 4, 1932  57: September 5, 1932 - November 15, 1932  58: November 16, 1932 - January 12, 1933  59: January 13, 1933 - March 9, 1933  60: March 10, 1933 - April 26, 1933  61: April 27, 1933 - October 7, 1933  62: October 8, 1933 - January 17, 1934  63: January 18, 1934 - May 19, 1934  64: May 20, 1934 - September 15, 1934  65: September 16, 1934 - December 15, 1934  66: December 16, 1934 - April 24, 1935  67: April 25, 1935 - September 22, 1935  68: September 23, 1935 - May 15, 1936  69: May 16, 1936 - October 19, 1936  70: October 21, 1936 - February 24, 1937  71:  February 25, 1937 - July 5, 1937  72: July 6, 1937 - February 20, 1938  73: February 21, 1938 - September 8, 1938  74: September 9, 1938 - January 29, 1939  75: January 30, 1939 - May 30, 1939