Series members 11–21 occur between 1901 and 2100: 11 12 13 Jul 30, 1916 Aug 10, 1934 Aug 20, 1952 14 15 16 Aug 31, 1970 Sep 11, 1988 Sep 22, 2006 17 18 19 Oct 2, 2024 Oct 14, 2042 Oct 24, 2060 20 21 Nov 4, 2078 Nov 15, 2096