Year Annual 15-year moving average
1720 130.0
1721 130.0
1722 78.0
1723 220.0
1724 78.0
1725 79.0
1726 360.0
1727 132.0 173.267
1728 220.0 169.933
1729 281.0 176.0
1730 79.0 179.533
1731 279.0 183.933
1732 220.0 193.2
1733 182.0 215.933
1734 131.0 199.6
1735 80.0 197.8
1736 221.0 189.133
1737 131.0 177.667
1738 286.0 193.067
1739 217.0 190.8
1740 420.0 202.8
1741 115.0 210.667
1742 105.0 223.067
1743 90.0 223.333
1744 109.0 233.933
1745 310.0 241.2
1746 245.0 229.467
1747 400.0 243.0
1748 300.0 237.0
1749 317.0 236.0
1750 84.0 254.4
1751 380.0 272.4
1752 240.0 271.8
1753 110.0 276.467
1754 420.0 270.533
1755 330.0 255.2
1756 100.0 243.467
1757 381.0 228.333
1758 360.0 234.733
1759 100.0 224.733
1760 380.0 230.333
1761 156.0 244.333
1762 170.0 222.333
1763 124.0 224.333
1764 90.0 239.667
1765 180.0 237.2
1766 230.0 219.867
1767 324.0 232.6
1768 320.0 226.0
1769 90.0 229.6
1770 360.0 236.933
1771 330.0 242.0
1772 344.0 243.333
1773 100.0 250.6
1774 291.0 251.067
1775 281.0 249.467
1776 210.0 244.8
1777 280.0 264.133
1778 200.0 264.133
1779 110.0 267.467
1780 289.0 263.2
1781 237.0 277.867
1782 300.0 286.467
1783 250.0 272.4
1784 380.0 263.733
1785 360.0 262.4
1786 380.0 255.733
1787 280.0 255.067
1788 320.0 257.8
1789 420.0 252.4
1790 70.0 242.533
1791 80.0 235.333
1792 260.0 238.0
1793 100.0 240.667
1794 100.0 224.4
1795 330.0 221.733
1796 156.0 227.067
1797 152.0 220.4
1798 142.0 242.4
1799 420.0 253.8
1800 400.0 245.8
1801 136.0 257.8
1802 240.0 279.133
1803 400.0 278.133
1804 320.0 282.4
1805 400.0 288.267
1806 251.0 298.8
1807 140.0 297.467
1808 280.0 281.467
1809 420.0 292.4
1810 315.0 282.4
1811 220.0 273.6
1812 240.0 257.6
1813 300.0 255.6
1814 400.0 256.2
1815 160.0 251.933
1816 300.0 244.933
1817 90.0 222.533
1818 268.0 207.933
1819 80.0 203.933
1820 370.0 204.6
1821 260.0 203.333
1822 76.0 202.0
1823 175.0 219.333
1824 84.0 221.2
1825 96.0 222.2
1826 160.0 210.0
1827 250.0 220.2
1828 281.0 200.2
1829 380.0 208.867
1830 420.0 215.267
1831 328.0 230.933
1832 105.0 247.0
1833 85.0 264.733
1834 233.0 279.2
1835 70.0 267.867
1836 390.0 255.133
1837 172.0 255.333
1838 410.0 253.733
1839 325.0 243.867
1840 362.0 255.533
1841 377.0 258.533
1842 80.0 255.133
1843 90.0 272.467
1844 383.0 258.467
1845 396.0 258.533
1846 180.0 251.533
1847 280.0 238.333
1848 130.0 234.467
1849 182.0 237.0
1850 330.0 246.0
1851 180.0 246.0
1852 173.0 225.8
1853 305.0 211.4
1854 127.0 220.4
1855 304.0 224.2
1856 415.0 221.533
1857 215.0 214.733
1858 90.0 216.733
1859 80.0 211.667
1860 180.0 228.133
1861 315.0 235.267
1862 337.0 235.6
1863 90.0 227.2
1864 80.0 227.533
1865 360.0 220.933
1866 104.0 220.933
1867 420.0 221.467
1868 412.0 231.467
1869 132.0 237.933
1870 178.0 243.467
1871 420.0 242.267
1872 116.0 246.267
1873 90.0 230.6
1874 88.0 251.667
1875 330.0 229.067
1876 412.0 224.067
1877 420.0 223.733
1878 72.0 222.4
1879 140.0 207.6
1880 125.0 205.533
1881 420.0 227.533
1882 81.0 243.467
1883 337.0 226.867
1884 127.0 207.8
1885 158.0 196.6
1886 198.0 219.8
1887 85.0 215.867
1888 420.0 226.333
1889 327.0 207.867
1890 81.0 214.467
1891 126.0 201.333
1892 252.0 205.067
1893 420.0 216.533
1894 81.0 215.333
1895 282.0 233.667
1896 143.0 211.8
1897 180.0 201.733
1898 140.0 205.267
1899 183.0 202.533
1900 330.0 195.0
1901 180.0 182.667
1902 360.0 189.333
1903 92.0 175.933
1904 176.0 173.733
1905 134.0 172.467
1906 85.0 171.0
1907 139.0 167.267
1908 235.0 157.467
1909 181.0 167.467
1910 81.0 170.133
1911 110.0 174.733
1912 161.0 173.0
1913 118.0 174.133
1914 127.0 176.8
1915 183.0 184.867
1916 330.0 191.2
1917 400.0 197.8
1918 161.0 198.067
1919 150.0 216.2
1920 151.0 213.867
1921 125.0 218.0
1922 260.0 235.533
1923 330.0 227.2
1924 280.0 216.867
1925 85.0 200.067
1926 382.0 199.2
1927 126.0 196.533
1928 180.0 192.467
1929 390.0 194.0
1930 58.0 187.4
1931 175.0 170.067
1932 148.0 155.467
1933 148.0 177.8
1934 110.0 177.067
1935 90.0 196.667
1936 148.0 190.267
1937 161.0 168.533
1938 70.0 171.933
1939 61.0 174.6
1940 420.0 192.733
1941 371.0 196.267
1942 420.0 193.067
1943 84.0 194.6
1944 64.0 194.667
1945 109.0 191.933
1946 215.0 197.467
1947 420.0 211.533
1948 201.0 193.667
1949 62.0 195.467
1950 113.0 178.733
1951 149.0 186.2
1952 120.0 187.933
1953 153.0 195.867
1954 272.0 185.933
1955 152.0 169.933
1956 398.0 178.467
1957 169.0 186.667
1958 196.0 193.2
1959 90.0 206.133
1960 228.0 211.733
1961 66.0 215.733
1962 180.0 213.667
1963 329.0 224.467
1964 185.0 210.333
1965 211.0 212.0
1966 343.0 205.0
1967 204.0 205.4
1968 213.0 195.2
1969 241.0 203.867
1970 314.0 205.533
1971 186.0 197.933
1972 194.0 206.867
1973 91.0 210.2
1974 96.0 201.067
1975 75.0 203.267
1976 196.0 198.067
1977 205.0 195.2
1978 215.0 198.867
1979 319.0 208.733
1980 261.0 222.933
1981 206.0 227.067
1982 237.0 224.667
1983 135.0 224.333
1984 198.0 219.667
1985 369.0 210.933
1986 334.0 203.133
1987 407.0 196.6
1988 153.0 184.267
1989 60.0 188.2
1990 70.0 181.0
1991 126.0 180.667
1992 74.0 177.933
1993 98.0 159.733
1994 221.0 146.067
1995 76.0 125.733
1996 265.0 131.067
1997 129.0 137.267
1998 130.0 144.467
1999 157.0 150.133
2000 96.0 154.533
2001 129.0 151.267
2002 102.0 143.867
2003 233.0 155.067
2004 153.0 158.0
2005 178.0 161.333
2006 211.0 164.667
2007 140.0
2008 49.0
2009 110.0
2010 244.0
2011 309.0
2012 179.0
2013 180.0