COMBINED MONTHLY MEAN SUNSPOT NUMBERS =============================================================================== Year Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec ------------------------------------------------------------------------------- 1749 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 81.6 82.8 84.1 86.3 87.8 88.7 1750 89.0 90.2 92.3 92.6 88.2 83.8 83.3 81.8 78.6 75.4 72.9 69.6 1751 66.8 64.2 59.5 54.9 51.7 49.0 46.2 45.0 46.4 47.5 47.6 47.1 1752 47.2 46.4 45.3 46.4 47.8 48.0 48.2 47.8 46.0 44.1 42.2 40.9 1753 38.2 36.2 36.7 35.8 34.2 32.1 28.8 25.8 22.8 19.9 18.3 17.4 1754 17.1 15.8 13.9 13.0 12.7 12.3 12.6 13.4 14.0 13.9 12.7 10.7 1755 9.2 8.4 8.4 8.8 8.5 8.9 9.7 9.6 9.4 9.4 10.1 11.1 1756 11.5 11.4 11.3 10.6 10.7 10.6 10.3 10.9 12.4 14.1 16.0 17.1 1757 18.0 20.7 23.8 25.7 28.4 31.4 33.4 35.7 37.9 40.6 42.7 44.4 1758 46.5 46.8 47.2 48.4 47.7 47.2 48.0 48.2 47.7 46.6 45.6 46.0 1759 46.5 48.1 50.1 51.6 52.7 53.4 54.8 56.2 58.0 59.6 61.1 62.0 1760 62.5 63.3 62.8 61.8 62.0 62.7 63.0 64.4 66.0 66.8 68.8 72.4 1761 75.7 77.5 79.8 83.0 85.9 86.5 84.8 82.9 80.7 78.8 75.5 71.7 1762 68.3 64.8 62.5 60.4 59.0 59.8 61.7 60.5 58.3 56.7 55.3 53.2 1763 52.4 51.5 49.8 48.8 47.1 45.8 45.3 46.5 47.9 48.3 48.8 49.1 1764 47.8 46.9 45.4 43.0 40.8 37.8 34.9 32.0 29.9 28.8 27.3 25.8 1765 25.3 25.2 24.6 23.6 22.5 21.4 20.4 19.3 19.1 19.0 18.6 18.1 1766 16.4 14.4 12.8 12.0 11.2 11.2 12.1 13.5 14.5 15.9 17.2 18.6 1767 20.6 22.9 26.0 29.3 32.9 36.4 38.9 41.5 43.1 43.7 46.1 49.9 1768 53.0 55.4 57.8 60.6 63.5 67.4 70.7 71.5 72.1 75.1 77.2 77.8 1769 81.2 86.2 91.5 97.9 103.7 106.1 107.3 111.9 115.8 114.5 112.5 111.9 1770 111.1 110.9 109.3 105.2 102.3 101.2 98.0 91.1 85.7 84.9 88.9 93.9 1771 93.6 89.0 86.1 85.4 83.5 81.9 84.3 88.9 90.1 90.5 86.9 79.5 1772 77.3 77.6 75.4 72.8 70.7 67.8 64.6 60.1 58.3 56.7 54.3 53.3 1773 50.0 46.1 43.5 40.4 37.4 35.6 34.5 35.6 37.3 38.0 38.9 39.3 1774 38.9 38.2 37.1 35.6 34.2 31.9 28.9 24.4 19.8 16.6 13.3 10.6 1775 9.3 8.6 8.5 7.9 7.5 7.2 7.7 8.9 9.2 9.4 10.2 10.7 1776 11.0 11.7 12.9 14.5 16.3 18.5 20.8 22.8 25.2 29.6 35.6 41.0 1777 47.5 55.1 62.9 70.3 78.1 87.6 98.0 106.6 113.6 119.6 128.2 138.6 1778 144.8 148.4 151.9 156.3 158.5 156.5 151.8 151.5 153.2 152.5 148.4 141.9 1779 139.0 137.5 133.8 129.9 127.0 125.7 124.1 119.4 115.7 112.8 109.4 106.9 1780 103.5 100.0 98.2 95.5 91.3 86.9 86.0 86.2 83.4 80.4 79.2 79.5 1781 79.4 78.0 75.4 71.5 69.8 69.1 66.2 62.8 60.6 58.8 55.6 51.0 1782 47.0 44.5 42.9 42.0 40.4 38.7 37.4 36.3 36.0 35.0 33.2 31.3 1783 30.6 29.4 27.7 26.4 25.1 23.6 22.2 20.3 18.3 16.9 15.5 14.1 1784 12.3 10.8 10.0 9.7 9.8 10.0 9.9 9.6 9.5 9.7 10.5 11.9 1785 13.9 15.5 16.9 19.4 22.0 23.5 25.4 28.3 31.6 36.1 42.0 46.3 1786 49.6 54.5 60.7 66.7 72.6 79.3 86.9 93.4 97.5 100.9 104.4 107.9 1787 111.4 115.3 119.2 122.9 125.9 129.5 132.2 133.3 136.6 138.1 136.4 137.8 1788 140.7 141.2 140.4 139.1 136.6 132.8 129.9 128.7 127.6 127.3 128.3 127.3 1789 124.9 122.5 119.9 116.5 116.0 117.9 117.7 117.3 116.4 114.2 111.7 109.2 1790 106.0 103.4 101.2 99.6 97.2 92.5 88.6 84.6 81.0 79.4 77.8 75.9 1791 74.9 73.1 70.8 69.4 67.9 66.9 66.0 65.4 65.1 64.5 64.0 63.4 1792 62.2 61.9 62.2 61.8 61.3 60.5 60.0 59.5 58.8 57.6 56.2 55.4 1793 55.1 54.0 51.3 49.3 48.3 47.3 46.4 45.5 44.3 42.6 41.7 41.4 1794 40.7 40.7 40.7 39.3 39.6 40.8 40.0 38.9 37.6 36.2 34.7 32.7 1795 30.5 28.7 28.2 28.0 25.8 22.7 21.3 20.6 20.1 20.8 20.9 20.1 1796 20.2 19.8 19.0 18.8 17.8 16.6 15.7 14.6 13.3 11.6 9.9 9.5 1797 8.8 8.0 7.7 7.0 6.7 6.5 5.9 5.4 5.7 5.9 5.5 4.7 1798 4.1 3.8 3.5 3.2 3.2 3.8 4.0 4.4 5.1 5.8 6.5 7.3 1799 7.8 7.7 7.5 7.6 7.3 6.8 7.0 7.1 6.6 5.9 5.4 5.9 1800 7.2 8.8 10.1 10.9 11.5 13.2 15.3 17.0 18.5 20.4 22.8 24.3 1801 25.2 26.6 28.3 30.0 32.1 33.7 34.9 36.5 37.7 38.6 39.6 40.7 1802 41.8 42.8 44.1 45.1 45.1 45.0 45.1 45.4 45.1 43.9 43.2 42.8 1803 42.4 41.7 40.8 41.2 42.5 43.1 42.9 42.6 43.2 45.1 45.7 45.2 1804 44.3 43.9 44.6 45.3 46.1 47.0 48.1 48.6 48.6 48.2 47.9 48.3 1805 48.9 49.2 48.8 47.1 44.9 43.1 41.3 39.8 38.4 37.2 36.3 35.2 1806 34.2 33.2 31.7 30.7 30.0 28.7 27.0 25.1 23.4 22.3 21.5 20.2 1807 18.9 17.6 16.3 14.7 13.0 11.1 9.5 8.7 8.0 7.1 6.8 7.0 1808 6.8 6.4 6.5 6.6 6.8 7.6 8.4 8.9 9.2 8.8 7.9 7.2 1809 6.7 6.1 5.3 4.6 4.0 3.0 2.2 1.6 1.1 1.0 0.8 0.4 1810 0.1 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 1811 0.3 0.6 0.7 1.0 1.3 1.4 1.9 2.4 2.5 2.6 2.6 2.7 1812 2.5 2.9 3.7 3.7 3.9 4.6 4.5 4.4 4.8 5.5 6.4 7.0 1813 8.1 8.6 8.7 10.1 11.5 12.0 13.1 14.1 14.3 14.8 15.1 15.3 1814 15.4 15.2 14.6 14.0 13.5 13.7 13.8 14.5 16.2 17.4 17.9 19.8 1815 22.2 24.8 27.6 29.2 30.7 33.5 35.7 37.5 41.0 44.1 46.7 47.6 1816 47.3 46.4 46.1 47.7 48.7 47.3 46.2 46.2 46.7 46.3 44.0 42.8 1817 43.2 44.5 45.0 43.2 41.6 41.1 41.0 39.5 35.0 32.4 34.1 35.3 1818 34.2 32.7 31.7 31.5 31.0 30.2 30.0 29.8 28.8 27.3 25.3 23.9 1819 24.0 23.9 23.2 22.6 23.0 23.8 23.4 23.1 23.4 23.4 23.7 23.1 1820 21.7 21.2 20.8 19.6 18.1 16.5 15.7 14.9 14.0 13.6 12.0 10.5 1821 9.4 7.8 6.8 7.2 7.5 7.0 5.7 4.7 5.0 5.6 5.8 5.9 1822 6.3 6.4 6.1 5.2 4.2 4.0 4.0 4.0 3.3 2.1 1.4 1.2 1823 0.6 0.2 0.1 0.1 0.1 0.9 2.7 4.0 4.5 5.3 6.2 6.3 1824 6.3 6.3 7.2 9.1 10.2 9.4 7.9 7.4 8.5 8.8 8.6 9.8 1825 11.7 14.0 14.9 14.3 14.3 15.7 17.1 17.8 18.5 19.9 21.5 23.1 1826 24.9 26.4 27.1 28.7 31.3 34.4 37.0 38.9 41.0 42.8 44.7 46.5 1827 46.9 47.1 48.9 50.4 51.0 50.5 50.3 51.8 52.8 53.7 55.7 58.8 1828 61.0 62.5 63.5 63.4 63.7 64.1 63.8 62.7 62.4 64.1 64.6 62.7 1829 63.2 64.8 65.0 65.2 65.7 66.6 67.3 68.7 70.1 71.1 71.5 71.1 1830 68.8 65.7 65.0 66.5 68.2 69.9 70.7 69.6 69.1 67.3 63.9 61.4 1831 60.2 60.4 59.6 57.0 53.8 50.0 47.1 46.7 45.3 42.6 41.5 41.4 1832 39.8 36.6 33.4 31.1 28.9 27.6 26.7 24.2 20.7 17.9 15.7 13.5 1833 12.1 11.7 11.7 11.3 10.3 9.3 8.3 8.1 7.9 7.5 7.3 7.4 1834 7.8 7.8 7.7 8.4 10.2 12.2 13.4 13.7 14.7 17.8 21.8 24.3 1835 27.5 31.9 37.9 44.6 50.4 55.1 60.2 67.1 73.8 80.5 86.7 93.3 1836 99.5 103.9 105.7 107.2 109.9 116.1 125.6 132.6 136.9 138.2 138.1 139.5 1837 142.8 145.8 146.9 146.4 145.3 141.5 136.5 130.9 127.4 127.2 127.8 126.2 1838 121.3 116.7 113.5 111.2 108.6 105.2 101.5 100.6 98.7 93.4 87.2 82.0 1839 79.4 80.6 85.3 87.7 87.4 86.3 84.7 83.0 82.0 81.8 82.6 83.0 1840 81.7 77.6 72.1 68.2 66.1 65.1 62.3 57.5 53.5 50.8 49.7 49.9 1841 49.0 47.0 44.6 42.0 39.4 37.4 36.6 36.1 35.4 34.6 32.2 29.0 1842 26.8 25.5 24.2 23.8 25.1 25.1 23.9 22.8 21.5 20.2 19.3 18.8 1843 18.2 17.5 16.3 14.3 12.0 10.9 10.6 10.9 11.6 12.3 12.3 11.7 1844 11.9 12.8 13.5 14.3 14.6 14.6 15.7 17.5 20.0 22.7 25.7 28.4 1845 29.9 30.7 32.0 33.7 35.7 38.5 40.6 41.5 42.6 44.0 45.0 46.9 1846 49.0 50.6 54.8 58.6 60.2 61.3 62.5 63.2 63.9 63.8 63.4 64.9 1847 66.0 69.8 75.6 83.0 91.5 96.6 102.5 109.3 113.0 116.6 120.3 123.2 1848 128.7 132.0 129.1 124.6 121.6 122.6 124.6 125.4 125.7 125.0 123.9 121.0 1849 116.4 111.2 108.2 105.4 102.2 98.9 93.0 88.0 85.7 82.7 79.4 78.2 1850 76.1 74.2 73.7 73.3 71.5 68.1 66.5 67.1 67.0 66.8 67.3 67.1 1851 66.7 66.4 65.4 64.3 63.8 64.1 64.2 62.3 60.5 60.8 60.8 59.8 1852 59.4 58.9 56.9 55.8 56.2 55.2 53.0 50.9 48.9 47.2 45.6 44.5 1853 44.4 45.0 45.2 44.0 41.9 40.0 38.0 35.9 34.3 32.7 31.4 30.1 1854 28.2 25.6 23.7 22.0 20.8 20.7 20.5 20.0 19.5 18.4 16.9 15.6 1855 14.2 12.9 11.4 10.4 9.2 7.5 6.2 5.4 4.5 3.8 3.5 3.2 1856 3.3 3.6 3.9 3.9 3.8 4.1 4.9 5.5 5.8 6.2 7.6 9.2 1857 10.4 11.6 13.7 16.7 19.2 21.5 23.8 26.0 29.3 32.6 34.3 36.0 1858 38.6 41.7 44.8 48.5 51.5 53.6 56.7 60.7 64.3 67.6 71.7 75.5 1859 78.9 82.6 85.9 87.9 90.8 93.2 93.8 93.8 94.1 93.9 94.0 95.5 1860 97.3 98.0 97.1 95.5 94.5 95.2 95.0 93.7 93.3 94.5 93.6 90.6 1861 88.2 85.8 84.5 83.1 80.3 77.8 77.2 76.7 73.8 69.5 68.0 68.1 1862 67.7 66.7 65.3 63.7 62.5 60.8 58.5 57.5 58.2 58.6 57.6 55.3 1863 51.8 49.6 47.1 45.1 44.5 44.0 44.4 44.4 44.0 43.8 43.0 43.2 1864 44.8 46.0 46.6 46.6 47.2 47.5 46.6 45.9 44.4 43.1 42.5 41.3 1865 39.1 37.2 36.2 35.2 33.2 31.1 29.8 29.0 28.4 27.2 25.8 24.2 1866 22.8 21.0 19.4 18.7 17.9 16.8 15.0 12.1 9.9 8.7 7.8 6.7 1867 5.9 5.4 5.2 5.3 5.3 6.3 7.9 9.2 10.5 12.6 14.9 17.1 1868 19.3 21.6 24.4 27.9 32.0 35.8 39.5 43.2 46.1 47.4 50.8 57.3 1869 61.7 64.9 68.2 69.4 70.1 72.5 74.7 77.7 84.3 93.6 101.6 105.7 1870 109.9 116.1 121.5 127.4 133.9 137.9 139.4 140.3 140.1 139.6 138.5 135.4 1871 132.3 129.3 125.1 120.4 116.3 112.9 110.9 110.3 107.8 103.0 98.9 98.1 1872 98.9 98.3 99.0 101.0 101.9 101.9 101.9 101.6 101.5 100.8 97.3 92.1 1873 87.8 85.1 81.3 76.2 71.5 67.7 65.2 62.3 58.3 54.3 52.4 52.0 1874 51.7 51.5 50.4 49.1 47.4 45.5 42.7 39.0 36.7 36.1 34.6 32.6 1875 29.7 25.4 22.4 20.5 19.1 17.8 17.0 16.7 16.3 15.1 13.7 12.5 1876 11.7 11.5 11.6 12.0 11.7 11.3 11.7 11.8 10.8 10.6 11.8 13.1 1877 13.2 12.7 12.9 12.9 12.7 12.7 11.5 10.6 10.3 9.5 8.2 7.2 1878 6.6 6.1 5.4 4.7 4.0 3.5 3.3 3.0 2.4 2.3 2.5 2.2 1879 2.5 3.2 3.7 4.2 5.1 5.7 7.0 9.0 10.9 12.3 13.7 15.8 1880 17.7 19.8 23.9 27.6 29.7 31.3 32.8 34.4 36.8 39.5 41.6 43.6 1881 47.0 49.7 49.6 49.9 51.8 53.6 54.7 55.7 57.0 59.5 62.2 62.4 1882 60.5 58.4 57.8 57.8 58.8 59.8 60.3 60.0 58.0 56.5 54.5 54.5 1883 57.2 58.9 58.9 59.8 60.8 62.2 64.9 67.9 71.4 73.0 74.2 74.6 1884 72.4 71.7 72.5 71.4 67.9 64.7 61.5 58.8 56.6 54.2 53.6 55.2 1885 57.1 57.4 56.2 54.9 54.3 53.0 51.4 49.0 47.4 47.2 45.0 40.9 1886 37.0 34.1 32.0 30.0 27.4 25.8 24.6 23.3 20.5 16.8 14.8 13.9 1887 13.1 13.0 12.6 12.0 12.1 12.7 13.2 13.0 12.9 13.0 12.4 11.5 1888 10.3 8.6 7.9 7.8 7.8 7.3 6.3 5.8 5.8 5.8 5.5 5.3 1889 5.5 6.5 7.2 7.1 6.7 6.2 6.4 6.3 5.9 5.7 5.7 5.6 1890 5.4 5.0 5.0 5.8 6.6 7.0 7.4 8.6 9.8 10.8 13.1 16.5 1891 20.5 23.4 26.0 29.2 32.2 34.6 37.9 42.5 46.4 50.0 53.7 56.5 1892 58.4 62.0 65.2 66.4 68.1 71.0 73.2 73.3 73.9 75.3 76.3 77.1 1893 78.1 79.8 81.6 82.6 83.4 84.5 85.4 86.3 86.2 85.3 85.8 86.8 1894 87.9 86.2 83.2 82.6 81.6 79.4 77.2 75.6 75.3 75.4 73.8 71.3 1895 67.7 65.2 64.8 64.2 63.5 63.5 62.5 60.7 59.9 58.2 55.1 52.5 1896 51.5 49.6 48.0 46.6 44.5 43.0 42.3 41.6 39.5 38.0 37.1 35.3 1897 33.0 32.0 31.2 30.1 28.3 26.6 25.8 25.7 26.3 26.0 25.6 26.3 1898 26.0 25.6 25.4 25.7 27.5 27.6 26.3 24.7 22.7 21.9 21.1 20.3 1899 20.4 19.4 17.1 15.1 13.2 12.2 11.7 11.5 11.2 10.9 11.3 11.3 1900 10.7 10.5 10.6 10.6 10.4 9.9 9.1 8.2 7.6 6.8 5.9 5.4 1901 4.8 4.4 3.9 3.2 2.8 2.8 3.0 3.1 3.3 3.6 3.3 2.8 1902 2.7 2.7 3.1 3.9 4.7 5.0 5.2 6.0 6.7 7.9 9.5 10.6 1903 12.3 14.5 15.8 16.9 19.3 22.5 25.4 26.6 27.9 29.6 31.4 33.5 1904 35.5 37.7 39.7 41.1 41.5 41.6 42.9 46.4 49.8 50.4 50.6 51.3 1905 52.5 53.5 54.5 56.6 60.5 63.4 63.1 60.4 58.5 59.5 60.6 61.6 1906 63.4 64.2 63.8 61.3 55.9 53.5 55.1 59.6 62.7 62.4 61.7 60.1 1907 56.9 55.0 56.4 59.6 62.5 62.8 60.5 55.8 51.4 50.3 50.4 50.6 1908 50.5 51.6 53.2 51.9 49.9 48.9 49.3 50.5 52.6 53.1 51.9 50.6 1909 49.4 46.4 41.6 40.7 42.2 43.3 42.6 40.7 38.2 35.4 33.8 32.8 1910 31.5 30.1 29.1 27.7 24.7 20.6 17.6 15.7 14.2 14.0 13.8 12.8 1911 12.0 11.2 10.0 7.5 6.0 5.9 5.6 5.1 4.6 4.0 3.3 3.1 1912 3.2 3.0 3.1 3.4 3.4 3.4 3.7 3.9 3.8 3.5 3.2 2.8 1913 2.6 2.5 2.2 1.8 1.7 1.5 1.5 1.5 1.6 2.4 3.3 4.0 1914 4.6 5.0 5.8 6.5 7.4 8.8 10.4 12.9 16.1 18.6 20.7 24.3 1915 29.4 34.8 38.9 42.3 45.3 46.9 48.3 49.8 51.5 53.9 56.9 58.6 1916 57.8 55.6 54.0 53.7 54.6 56.3 58.3 60.2 62.1 63.3 65.1 68.7 1917 73.4 81.2 89.7 94.1 96.3 100.7 104.8 105.4 104.2 103.5 102.2 98.3 1918 95.5 92.8 88.5 87.0 87.0 83.5 78.6 77.2 77.5 76.1 75.4 78.0 1919 78.4 75.2 72.8 70.4 67.4 64.6 63.7 62.8 61.9 60.5 56.7 51.4 1920 46.8 43.2 40.3 39.4 38.7 37.9 36.8 34.9 32.1 31.0 31.3 30.6 1921 31.0 31.7 31.1 29.0 27.3 26.5 25.3 24.4 25.5 25.8 24.3 22.5 1922 20.1 18.1 16.9 15.8 14.9 14.4 13.9 12.6 9.4 7.1 6.7 6.6 1923 6.4 5.9 6.0 6.6 6.9 6.4 5.6 5.6 5.7 5.8 6.8 8.1 1924 9.8 11.6 12.9 14.0 15.1 16.1 16.9 17.9 19.3 20.8 22.6 24.5 1925 25.9 27.1 29.4 32.6 36.0 40.9 47.1 51.8 55.6 57.7 58.9 60.9 1926 62.5 64.1 65.1 65.2 65.4 64.7 64.3 65.7 66.9 69.5 72.4 72.4 1927 71.9 71.7 71.7 71.7 71.6 70.5 69.1 68.4 68.2 68.4 67.7 69.0 1928 72.1 75.2 77.3 78.1 77.4 77.2 77.2 76.1 74.2 71.6 69.7 68.1 1929 66.1 64.2 61.1 58.5 59.5 62.8 64.7 64.0 62.9 61.6 60.1 57.4 1930 53.6 49.9 48.1 47.2 44.5 39.1 33.6 31.2 30.7 30.2 29.4 28.4 1931 27.6 26.9 25.9 24.3 22.6 21.6 21.1 19.7 17.5 15.9 14.8 14.8 1932 14.8 14.2 13.3 12.6 12.1 11.4 11.2 11.6 12.1 11.7 10.7 9.4 1933 8.4 7.9 7.6 7.4 6.9 6.1 5.3 4.3 3.5 3.6 4.6 5.4 1934 5.7 6.3 6.6 6.7 7.1 8.1 9.3 10.5 11.8 12.6 13.0 14.9 1935 17.6 19.5 22.0 25.6 29.9 34.1 37.9 42.0 46.5 51.3 55.1 57.2 1936 59.0 62.1 65.9 68.8 72.4 77.2 82.6 87.8 90.3 92.1 96.1 101.2 1937 107.6 113.5 116.7 119.2 119.0 115.8 113.0 111.2 110.9 110.7 110.8 109.8 1938 109.3 109.2 107.9 106.3 107.2 109.4 108.8 106.3 103.6 103.1 103.0 102.8 1939 100.1 96.9 97.4 97.9 95.2 90.9 87.5 85.5 85.5 84.3 79.6 76.3 1940 74.3 73.0 71.1 67.8 66.0 66.7 67.6 66.8 64.6 61.9 59.7 57.7 1941 56.6 54.7 52.8 52.4 51.2 48.9 47.1 47.0 47.7 49.2 50.1 47.9 1942 43.9 40.2 36.5 33.3 31.9 31.1 29.6 27.7 25.6 23.0 21.1 20.5 1943 20.2 19.9 19.6 18.8 17.5 16.5 16.0 14.4 12.5 10.8 9.2 8.6 1944 8.2 7.7 7.8 8.4 8.8 9.2 10.2 11.3 12.3 14.0 16.5 19.0 1945 21.9 23.8 25.1 28.1 31.7 33.1 34.3 38.6 43.9 48.1 52.1 56.0 1946 60.6 67.0 72.9 76.8 81.4 88.6 95.3 100.1 104.3 109.6 117.6 126.2 1947 131.7 136.8 143.4 149.0 151.8 151.7 151.2 148.9 145.5 145.7 146.2 145.3 1948 144.8 142.8 140.5 138.2 135.8 135.3 136.6 141.1 147.7 148.5 143.9 139.2 1949 136.6 134.5 133.2 133.0 134.8 136.0 134.4 130.0 124.4 121.0 119.6 118.0 1950 115.0 111.9 106.4 99.5 92.9 86.6 82.2 79.0 75.3 72.2 71.4 72.3 1951 71.7 69.5 69.8 70.7 70.2 69.8 68.6 66.3 63.3 59.2 53.0 46.8 1952 43.2 42.0 39.5 36.1 33.6 31.9 30.8 29.4 28.2 27.6 27.1 26.0 1953 24.1 21.6 19.9 18.9 17.4 15.2 12.8 11.5 11.4 10.4 8.8 7.4 1954 6.4 5.6 4.2 3.4 3.7 4.2 5.4 7.2 7.8 7.9 9.5 12.0 1955 14.2 16.4 19.5 23.4 28.8 35.1 40.1 46.5 55.5 64.4 73.0 81.0 1956 88.8 98.5 109.3 118.7 127.4 136.9 145.5 149.6 151.5 155.8 159.6 164.3 1957 170.2 172.2 174.3 181.0 185.5 187.9 191.4 194.4 197.3 199.5 200.8 200.0 1958 199.0 200.9 201.3 196.8 191.4 186.8 185.2 184.9 183.8 182.2 180.7 180.5 1959 178.6 176.9 174.5 169.2 165.1 161.4 155.8 151.3 146.3 141.1 137.2 132.5 1960 128.9 125.0 121.6 119.6 117.0 113.9 108.6 102.4 97.9 93.3 87.9 83.7 1961 80.2 74.8 68.9 64.3 60.1 55.8 53.1 52.5 52.3 51.4 50.5 48.7 1962 45.2 41.8 39.8 39.4 39.2 38.3 36.8 34.9 32.7 30.8 30.0 29.8 1963 29.4 29.8 29.7 29.1 28.7 28.2 27.7 27.2 26.9 26.0 23.8 21.3 1964 19.5 17.8 15.4 12.7 10.8 10.2 10.3 10.2 9.9 9.6 10.2 11.1 1965 11.7 12.0 12.5 13.6 14.6 15.0 15.5 16.4 17.4 19.7 22.3 24.5 1966 27.7 31.3 34.5 37.4 40.7 44.7 50.3 56.7 63.1 67.6 70.2 72.7 1967 75.0 78.8 82.2 84.6 87.5 91.3 94.1 95.3 95.3 95.0 97.1 100.6 1968 102.6 102.9 104.7 107.2 107.6 106.6 105.2 104.8 107.0 109.9 110.6 110.1 1969 110.0 109.6 108.0 106.4 106.2 106.1 105.9 106.5 105.4 104.1 104.6 104.9 1970 105.6 106.0 106.2 106.1 105.8 105.3 103.9 101.0 97.2 93.9 89.4 84.1 1971 80.4 77.8 74.4 70.9 68.1 66.7 65.4 64.6 65.8 66.2 66.8 69.4 1972 70.8 71.2 72.4 73.4 72.9 70.5 68.2 65.5 62.2 60.6 58.7 55.1 1973 50.9 46.5 44.2 42.7 40.7 39.1 37.5 36.1 34.4 32.6 31.8 31.5 1974 32.7 34.4 34.0 33.9 34.6 34.5 34.0 33.1 32.1 30.2 27.5 25.2 1975 23.0 22.1 21.2 18.6 16.8 16.0 15.0 14.3 14.4 15.4 16.1 16.3 1976 15.2 13.2 12.2 12.6 12.5 12.2 12.9 14.0 14.3 13.5 13.5 14.8 1977 16.7 18.1 20.0 22.2 24.2 26.3 29.0 33.4 39.1 45.6 51.9 56.9 1978 61.3 64.5 69.6 76.9 83.2 89.3 97.4 104.0 108.4 111.1 113.3 117.7 1979 123.7 130.9 136.5 141.1 147.3 153.0 155.0 155.4 155.7 157.8 162.3 164.5 1980 163.9 162.6 160.9 158.7 156.3 154.7 152.8 150.3 150.1 150.2 147.7 142.7 1981 140.3 141.5 143.0 143.4 142.9 141.5 140.3 141.1 142.8 142.2 138.8 137.8 1982 137.0 133.3 129.2 124.3 119.9 117.3 115.2 109.4 101.0 95.7 94.7 94.6 1983 92.8 90.3 85.9 81.5 77.1 70.5 65.5 65.8 67.9 68.2 66.8 64.0 1984 60.2 56.4 53.1 49.8 47.5 46.5 44.2 39.6 33.9 28.9 24.7 21.7 1985 20.5 19.6 18.6 18.3 18.3 18.0 17.4 17.1 17.3 17.3 16.8 15.3 1986 13.8 13.1 13.0 13.7 14.3 13.8 13.7 13.2 12.3 13.2 14.9 16.3 1987 17.6 19.6 22.1 24.4 26.5 28.4 31.3 34.8 39.0 43.6 46.7 51.3 1988 58.2 64.6 71.3 77.5 83.8 93.7 104.3 113.7 121.2 125.3 130.4 137.6 1989 142.0 145.0 149.7 153.5 156.9 158.4 158.5 157.7 156.6 157.4 157.5 153.5 1990 150.6 152.9 152.0 149.3 147.0 143.8 140.6 140.5 142.1 142.1 141.7 143.9 1991 147.6 147.6 146.6 146.5 145.5 145.2 146.3 146.6 144.9 141.7 138.1 131.7 1992 123.7 115.4 108.2 103.3 100.3 97.1 90.7 84.0 79.5 76.4 74.4 73.2 1993 71.4 69.3 66.6 63.6 59.9 56.1 54.7 52.3 48.4 44.9 41.2 38.4 1994 36.6 34.8 34.1 33.7 32.5 30.8 28.5 26.8 26.6 26.5 26.2 25.6 1995 24.2 23.0 22.1 20.6 19.2 18.2 17.0 15.4 13.4 12.1 11.3 10.8 1996 10.4 10.1 9.7 8.5 8.0 8.5 8.4 8.3 8.4 8.8 9.8 10.4 1997 10.5 11.0 13.5 16.5 18.3 20.3 22.6 25.0 28.3 31.8 35.0 39.0 1998 43.7 48.9 53.4 56.5 59.4 62.5 65.5 67.8 69.5 70.5 73.0 77.9 1999 82.6 84.6 83.8 85.5 90.5 93.1 94.3 97.5 102.3 107.8 111.0 111.1 2000 112.9 116.8 119.9 120.8 119.0 118.7 119.8 118.6 116.3 114.5 112.7 112.0 2001 108.7 104.0 104.8 107.5 108.6 109.8 111.7 113.6 114.1 114.0 115.5 114.6 2002 113.5 114.6 113.3 110.5 108.8 106.2 102.7 98.7 94.6 90.5 85.2 82.0 2003 80.8 78.3 74.0 70.1 67.6 65.0 61.8 60.0 59.5 58.2 56.7 54.8 2004 52.0 49.3 47.1 45.5 43.8 41.6 40.2 39.2 37.5 35.9 35.3 35.2 2005 34.6 33.9 33.5 31.6 28.9 28.8 29.1 27.4 25.8 25.5 24.9 23.0 2006 20.8 18.6 17.4 17.1 17.3 16.3 15.2 15.6 15.5 14.2 12.6 12.1 2007 11.9 11.5 10.7 9.8 8.6 7.6 6.9 6.0 5.9 6.0 5.7 4.9 2008 4.2 3.6 3.3 3.4 3.5 3.3 2.8 2.7 2.3 1.8 1.7 1.7 2009 1.8 1.9 2.0 2.2 2.3 2.7 3.6 4.8 6.2 7.1 7.6 8.3 2010 9.3 10.6 12.3 14.0 15.5 16.4 16.7 17.4 19.6 23.2 26.5 28.8 2011 30.9 33.4 36.9 41.8 47.6 53.2 57.3 59.0 59.5 59.9 61.1 63.4 2012 65.5 66.9 66.8 64.6 61.7 58.9 57.8 58.2 58.1 58.6 59.7 59.6 2013 58.7 58.4 57.6 57.9 59.9 62.6 65.5 68.9 73.0 74.9 75.3 75.9 2014 77.3 78.3 80.8 81.9 80.5 79.7 78.5 75.5 70.8 67.3 65.4 76.7 2015 62.5 60.3 57.5 55.2 53.3 50.5 47.8 46.5 46.1 45.0 42.8 40.5 2016 38.1 36.8 35.3 33.5 31.4 29.1 27.0 25.2 23.2 22.1 20.9 20.0 2017 19.5 18.6 18.0 17.4 16.3 15.5 14.7 13.7 12.7 11.6 10.7 10.2 2018 9.9 8.8 6.9 5.5 5.3 5.0 4.9 4.7 4.6 4.8 4.7 4.2 2019 2.9 2.7 2.6 2.4 2.2 1.7 1.4 1.5 1.7 1.9 2.2 2.5 -------------------------------------------------------------------------------- Last smoothed month using NOAA algorithm: 2014.11 Last NOAA smoothed mean month: 2014.12 WDC-SILSO V2.0 13-month smoothed solar index, scaled for IRI by 30%: 2015.01..2018.12 Predicted month start: 2018.11 NOAA approach: (prior to 2015.01): Each smoothed number represents the average of two adjacent 12-month running means of monthly means. Consider, for example, the June 1980 value. We built this number by first computing two 12-month means: one that averaged monthly means from December 1979 through November 1980 and a second that averaged means from January 1980 through December 1980. The June 1980 smoothed number equals the arithmetic average of these two running means. WDC-SILSO approach (since 2015.01): In June 2015, WDC-SILSO, Royal Observatory of Belgium, Brussels, adjusted their original observed sunspot numbers (Version 1.0) to a Version 2.0 series in which the sunspot numbers are higher. In the Version 1.0 data series, some of the sunspot numbers were weighted. The new (Version 2.0) sunspot numbers are unweighted sunspot number counts (for more information see: www.sidc.be/silso/home). The Bureau of Meteorology SWS solar cycle prediction is now based on the Version 2.0 values. As a result of the WDC-SILSO recalibration, the observed monthly sunspot numbers are higher. This is also reflected in the tables of smoothed sunspot numbers and equivalent 10.7 cm solar flux and the solar cycle graph. IRI approach using WDC-SILSO values (since 2015.01): Scale factor of 0.7