78 Year 712 Year 1311 Year 1336 Year 1347 Year 1398 Year 1451 Year 1459 Year 1498 Year 1500 Year 1505 Year 1527 Year 1529 Year 1538 Year 1541 Year 1555 Year 1556 Year 1561 Year 1564 Year 1573 Year 1574 Year 1576 Year 1586 Year 1597 Year 1600 Year 1601 Year 1602 Year 1604 Year 1608 Year 1609 Year 1612 Year 1621 Year 1639 Year 1640 Year 1641 Year 1645 Year 1648 Year 1654 Year 1656 Year 1657 Year 1658 Year 1659 Year 1661 Year 1663 Year 1664 Year 1665 Year 1671 Year 1672 Year 1674 Year 1675 Year 1677 Year 1678 Year 1679 Year 1681 Year 1684 Year 1686 Year 1687 Year 1689 Year 1690 Year 1698 Year 1702 Year 1705 Year 1708 Year 1715 Year 1731 Year 1739 Year 1746 Year 1748 Year 1752 Year 1753 Year 1754 Year 1756 Year 1757 Year 1758 Year 1759 Year 1760 Year 1762 Year 1763 Year 1764 Year 1768 Year 1769 Year 1772 Year 1774 Year 1775 Year 1776 Year 1780 Year 1781 Year 1782 Year 1784 Year 1785 Year 1786 Year 1789 Year 1790 Year 1792 Year 1793 Year 1795 Year 1796 Year 1798 Year 1799 Year 1801 Year 1802 Year 1803 Year 1805 Year 1810 Year 1815 Year 1818 Year 1820 Year 1823 Year 1824 Year 1827 Year 1829 Year 1831 Year 1835 Year 1839 Year 1842 Year 1845 Year 1846 Year 1848 Year 1851 Year 1852 Year 1854 Year 1855 Year 1856 Year 1857 Year 1858 Year 1859 Year 1860 Year 1861 Year 1863 Year 1869 Year 1870 Year 1873 Year 1874 Year 1875 Year 1878 Year 1879 Year 1880 Year 1881 Year 1883 Year 1885 Year 1886 Year 1887 Year 1888 Year 1890 Year 1891 Year 1894 Year 1895 Year 1896 Year 1898 Year 1899 Year 1901 Year 1902 Year 1903 Year 1904 Year 1905 Year 1906 Year 1907 Year 1908 Year 1909 Year 1910 Year 1911 Year 1912 Year 1913 Year 1914 Year 1915 Year 1917 Year 1918 Year 1919 Year 1920 Year 1921 Year 1922 Year 1923 Year 1924 Year 1925 Year 1926 Year 1927 Year 1928 Year 1929 Year 1930 Year 1931 Year 1932 Year 1933 Year 1934 Year 1935 Year 1936 Year 1938 Year 1939 Year 1940 Year 1941 Year 1942 Year 1943 Year 1944 Year 1945 Year 1946 Year 1947 Year 1948 Year 1949 Year 1950 Year 1951 Year 1952 Year 1953 Year 1954 Year 1955 Year 1956 Year 1957 Year 1958 Year 1959 Year 1960 Year 1961 Year 1962 Year 1963 Year 1964 Year 1965 Year 1966 Year 1967 Year 1968 Year 1969 Year 1970 Year 1971 Year 1972 Year 1973 Year 1974 Year 1975 Year 1976 Year 1977 Year 1978 Year 1979 Year 1980 Year 1981 Year 1982 Year 1983 Year 1984 Year 1985 Year 1986 Year 1987 Year 1988 Year 1989 Year 1990 Year 1991 Year 1992 Year 1993 Year 1994 Year 1995 Year 1996 Year 1997 Year 1998 Year 1999 Year 2000 Year 2001 Year

January
March
May
June
July
August
September
November
December

1- May-1972	All fuel coal mines were nationalised.