YEAR MATCHES (listed by MJD_DATE.EXE) (c) J R Stockton www.merlyn.demon.co.uk >= 1999-11-21 set-back.txt Matches of January 1st for years AD 1980-2030 Year from Day Feb29 12-month matches ... AD 1980-01-01 Tue TRUE = 1952 1924 1884 1856 1828 1788 1760 1732 1704 AD 1981-01-01 Thu FALSE = 1970 1959 1953 1942 1931 1925 1914 1903 1891 AD 1982-01-01 Fri FALSE = 1971 1965 1954 1943 1937 1926 1915 1909 1897 AD 1983-01-01 Sat FALSE = 1977 1966 1955 1949 1938 1927 1921 1910 1898 AD 1984-01-01 Sun TRUE = 1956 1928 1888 1860 1832 1804 1792 1764 1736 AD 1985-01-01 Tue FALSE = 1974 1963 1957 1946 1935 1929 1918 1907 1901 AD 1986-01-01 Wed FALSE = 1975 1969 1958 1947 1941 1930 1919 1913 1902 AD 1987-01-01 Thu FALSE = 1981 1970 1959 1953 1942 1931 1925 1914 1903 AD 1988-01-01 Fri TRUE = 1960 1932 1904 1892 1864 1836 1808 1796 1768 AD 1989-01-01 Sun FALSE = 1978 1967 1961 1950 1939 1933 1922 1911 1905 AD 1990-01-01 Mon FALSE = 1979 1973 1962 1951 1945 1934 1923 1917 1906 AD 1991-01-01 Tue FALSE = 1985 1974 1963 1957 1946 1935 1929 1918 1907 AD 1992-01-01 Wed TRUE = 1964 1936 1908 1896 1868 1840 1812 1772 1744 AD 1993-01-01 Fri FALSE = 1982 1971 1965 1954 1943 1937 1926 1915 1909 AD 1994-01-01 Sat FALSE = 1983 1977 1966 1955 1949 1938 1927 1921 1910 AD 1995-01-01 Sun FALSE = 1989 1978 1967 1961 1950 1939 1933 1922 1911 AD 1996-01-01 Mon TRUE = 1968 1940 1912 1872 1844 1816 1776 1748 1720 AD 1997-01-01 Wed FALSE = 1986 1975 1969 1958 1947 1941 1930 1919 1913 AD 1998-01-01 Thu FALSE = 1987 1981 1970 1959 1953 1942 1931 1925 1914 AD 1999-01-01 Fri FALSE = 1993 1982 1971 1965 1954 1943 1937 1926 1915 AD 2000-01-01 Sat TRUE = 1972 1944 1916 1876 1848 1820 1780 1752 1724 AD 2001-01-01 Mon FALSE = 1990 1979 1973 1962 1951 1945 1934 1923 1917 AD 2002-01-01 Tue FALSE = 1991 1985 1974 1963 1957 1946 1935 1929 1918 AD 2003-01-01 Wed FALSE = 1997 1986 1975 1969 1958 1947 1941 1930 1919 AD 2004-01-01 Thu TRUE = 1976 1948 1920 1880 1852 1824 1784 1756 1728 AD 2005-01-01 Sat FALSE = 1994 1983 1977 1966 1955 1949 1938 1927 1921 AD 2006-01-01 Sun FALSE = 1995 1989 1978 1967 1961 1950 1939 1933 1922 AD 2007-01-01 Mon FALSE = 2001 1990 1979 1973 1962 1951 1945 1934 1923 AD 2008-01-01 Tue TRUE = 1980 1952 1924 1884 1856 1828 1788 1760 1732 AD 2009-01-01 Thu FALSE = 1998 1987 1981 1970 1959 1953 1942 1931 1925 AD 2010-01-01 Fri FALSE = 1999 1993 1982 1971 1965 1954 1943 1937 1926 AD 2011-01-01 Sat FALSE = 2005 1994 1983 1977 1966 1955 1949 1938 1927 AD 2012-01-01 Sun TRUE = 1984 1956 1928 1888 1860 1832 1804 1792 1764 AD 2013-01-01 Tue FALSE = 2002 1991 1985 1974 1963 1957 1946 1935 1929 AD 2014-01-01 Wed FALSE = 2003 1997 1986 1975 1969 1958 1947 1941 1930 AD 2015-01-01 Thu FALSE = 2009 1998 1987 1981 1970 1959 1953 1942 1931 AD 2016-01-01 Fri TRUE = 1988 1960 1932 1904 1892 1864 1836 1808 1796 AD 2017-01-01 Sun FALSE = 2006 1995 1989 1978 1967 1961 1950 1939 1933 AD 2018-01-01 Mon FALSE = 2007 2001 1990 1979 1973 1962 1951 1945 1934 AD 2019-01-01 Tue FALSE = 2013 2002 1991 1985 1974 1963 1957 1946 1935 AD 2020-01-01 Wed TRUE = 1992 1964 1936 1908 1896 1868 1840 1812 1772 AD 2021-01-01 Fri FALSE = 2010 1999 1993 1982 1971 1965 1954 1943 1937 AD 2022-01-01 Sat FALSE = 2011 2005 1994 1983 1977 1966 1955 1949 1938 AD 2023-01-01 Sun FALSE = 2017 2006 1995 1989 1978 1967 1961 1950 1939 AD 2024-01-01 Mon TRUE = 1996 1968 1940 1912 1872 1844 1816 1776 1748 AD 2025-01-01 Wed FALSE = 2014 2003 1997 1986 1975 1969 1958 1947 1941 AD 2026-01-01 Thu FALSE = 2015 2009 1998 1987 1981 1970 1959 1953 1942 AD 2027-01-01 Fri FALSE = 2021 2010 1999 1993 1982 1971 1965 1954 1943 AD 2028-01-01 Sat TRUE = 2000 1972 1944 1916 1876 1848 1820 1780 1752 AD 2029-01-01 Mon FALSE = 2018 2007 2001 1990 1979 1973 1962 1951 1945 AD 2030-01-01 Tue FALSE = 2019 2013 2002 1991 1985 1974 1963 1957 1946 Note that Leap Years are hard to match (obviously); 2000 & 2004 are not matched by an earlier Leap Year in the range of a PC (1980 onwards). Therefore, read on Matches of March 1st for years AD 1980-2030 Year from Day Feb29 12-month matches (ignoring terminal Feb29) ... AD 1980-03-01 Sat FALSE = 1975 1969 1958 1952 1947 1941 1930 1924 1919 AD 1981-03-01 Sun FALSE = 1970 1964 1959 1953 1942 1936 1931 1925 1914 AD 1982-03-01 Mon FALSE = 1976 1971 1965 1954 1948 1943 1937 1926 1920 AD 1983-03-01 Tue TRUE = 1977 1966 1960 1955 1949 1938 1932 1927 1921 AD 1984-03-01 Thu FALSE = 1979 1973 1962 1956 1951 1945 1934 1928 1923 AD 1985-03-01 Fri FALSE = 1974 1968 1963 1957 1946 1940 1935 1929 1918 AD 1986-03-01 Sat FALSE = 1980 1975 1969 1958 1952 1947 1941 1930 1924 AD 1987-03-01 Sun TRUE = 1981 1970 1964 1959 1953 1942 1936 1931 1925 AD 1988-03-01 Tue FALSE = 1983 1977 1966 1960 1955 1949 1938 1932 1927 AD 1989-03-01 Wed FALSE = 1978 1972 1967 1961 1950 1944 1939 1933 1922 AD 1990-03-01 Thu FALSE = 1984 1979 1973 1962 1956 1951 1945 1934 1928 AD 1991-03-01 Fri TRUE = 1985 1974 1968 1963 1957 1946 1940 1935 1929 AD 1992-03-01 Sun FALSE = 1987 1981 1970 1964 1959 1953 1942 1936 1931 AD 1993-03-01 Mon FALSE = 1982 1976 1971 1965 1954 1948 1943 1937 1926 AD 1994-03-01 Tue FALSE = 1988 1983 1977 1966 1960 1955 1949 1938 1932 AD 1995-03-01 Wed TRUE = 1989 1978 1972 1967 1961 1950 1944 1939 1933 AD 1996-03-01 Fri FALSE = 1991 1985 1974 1968 1963 1957 1946 1940 1935 AD 1997-03-01 Sat FALSE = 1986 1980 1975 1969 1958 1952 1947 1941 1930 AD 1998-03-01 Sun FALSE = 1992 1987 1981 1970 1964 1959 1953 1942 1936 AD 1999-03-01 Mon TRUE = 1993 1982 1976 1971 1965 1954 1948 1943 1937 AD 2000-03-01 Wed FALSE = 1995 1989 1978 1972 1967 1961 1950 1944 1939 AD 2001-03-01 Thu FALSE = 1990 1984 1979 1973 1962 1956 1951 1945 1934 AD 2002-03-01 Fri FALSE = 1996 1991 1985 1974 1968 1963 1957 1946 1940 AD 2003-03-01 Sat TRUE = 1997 1986 1980 1975 1969 1958 1952 1947 1941 AD 2004-03-01 Mon FALSE = 1999 1993 1982 1976 1971 1965 1954 1948 1943 AD 2005-03-01 Tue FALSE = 1994 1988 1983 1977 1966 1960 1955 1949 1938 AD 2006-03-01 Wed FALSE = 2000 1995 1989 1978 1972 1967 1961 1950 1944 AD 2007-03-01 Thu TRUE = 2001 1990 1984 1979 1973 1962 1956 1951 1945 AD 2008-03-01 Sat FALSE = 2003 1997 1986 1980 1975 1969 1958 1952 1947 AD 2009-03-01 Sun FALSE = 1998 1992 1987 1981 1970 1964 1959 1953 1942 AD 2010-03-01 Mon FALSE = 2004 1999 1993 1982 1976 1971 1965 1954 1948 AD 2011-03-01 Tue TRUE = 2005 1994 1988 1983 1977 1966 1960 1955 1949 AD 2012-03-01 Thu FALSE = 2007 2001 1990 1984 1979 1973 1962 1956 1951 AD 2013-03-01 Fri FALSE = 2002 1996 1991 1985 1974 1968 1963 1957 1946 AD 2014-03-01 Sat FALSE = 2008 2003 1997 1986 1980 1975 1969 1958 1952 AD 2015-03-01 Sun TRUE = 2009 1998 1992 1987 1981 1970 1964 1959 1953 AD 2016-03-01 Tue FALSE = 2011 2005 1994 1988 1983 1977 1966 1960 1955 AD 2017-03-01 Wed FALSE = 2006 2000 1995 1989 1978 1972 1967 1961 1950 AD 2018-03-01 Thu FALSE = 2012 2007 2001 1990 1984 1979 1973 1962 1956 AD 2019-03-01 Fri TRUE = 2013 2002 1996 1991 1985 1974 1968 1963 1957 AD 2020-03-01 Sun FALSE = 2015 2009 1998 1992 1987 1981 1970 1964 1959 AD 2021-03-01 Mon FALSE = 2010 2004 1999 1993 1982 1976 1971 1965 1954 AD 2022-03-01 Tue FALSE = 2016 2011 2005 1994 1988 1983 1977 1966 1960 AD 2023-03-01 Wed TRUE = 2017 2006 2000 1995 1989 1978 1972 1967 1961 AD 2024-03-01 Fri FALSE = 2019 2013 2002 1996 1991 1985 1974 1968 1963 AD 2025-03-01 Sat FALSE = 2014 2008 2003 1997 1986 1980 1975 1969 1958 AD 2026-03-01 Sun FALSE = 2020 2015 2009 1998 1992 1987 1981 1970 1964 AD 2027-03-01 Mon TRUE = 2021 2010 2004 1999 1993 1982 1976 1971 1965 AD 2028-03-01 Wed FALSE = 2023 2017 2006 2000 1995 1989 1978 1972 1967 AD 2029-03-01 Thu FALSE = 2018 2012 2007 2001 1990 1984 1979 1973 1962 AD 2030-03-01 Fri FALSE = 2024 2019 2013 2002 1996 1991 1985 1974 1968 Years 2000, 2004 are no longer Leap, and have matches; Years 1999, 2003 are now Leap, and have matches (apart from the matchless February 29). Check interpretations against greg-cal.txt ---------