| Year | CW2011 | North Sea |
|---|---|---|
| 1807 | ||
| 1808 | ||
| 1809 | ||
| 1810 | ||
| 1811 | ||
| 1812 | ||
| 1813 | ||
| 1814 | ||
| 1815 | ||
| 1816 | ||
| 1817 | ||
| 1818 | ||
| 1819 | ||
| 1820 | ||
| 1821 | ||
| 1822 | ||
| 1823 | ||
| 1824 | ||
| 1825 | ||
| 1826 | ||
| 1827 | ||
| 1828 | ||
| 1829 | ||
| 1830 | ||
| 1831 | ||
| 1832 | ||
| 1833 | ||
| 1834 | ||
| 1835 | ||
| 1836 | ||
| 1837 | ||
| 1838 | ||
| 1839 | ||
| 1840 | ||
| 1841 | ||
| 1842 | ||
| 1843 | ||
| 1844 | ||
| 1845 | ||
| 1846 | ||
| 1847 | ||
| 1848 | ||
| 1849 | ||
| 1850 | ||
| 1851 | ||
| 1852 | ||
| 1853 | ||
| 1854 | ||
| 1855 | ||
| 1856 | ||
| 1857 | ||
| 1858 | ||
| 1859 | ||
| 1860 | ||
| 1861 | ||
| 1862 | ||
| 1863 | ||
| 1864 | ||
| 1865 | ||
| 1866 | ||
| 1867 | ||
| 1868 | ||
| 1869 | ||
| 1870 | ||
| 1871 | ||
| 1872 | ||
| 1873 | ||
| 1874 | ||
| 1875 | ||
| 1876 | ||
| 1877 | ||
| 1878 | ||
| 1879 | ||
| 1880 | -11.362 | -15.171 |
| 1881 | -15.367 | -14.611 |
| 1882 | -13.372 | -16.291 |
| 1883 | -15.088 | -15.761 |
| 1884 | -14.307 | -13.671 |
| 1885 | -14.778 | -13.821 |
| 1886 | -15.628 | -14.061 |
| 1887 | -17.731 | -14.621 |
| 1888 | -19.388 | -14.411 |
| 1889 | -17.333 | -14.251 |
| 1890 | -16.773 | -14.051 |
| 1891 | -15.878 | -14.221 |
| 1892 | -15.199 | -13.901 |
| 1893 | -12.543 | -13.431 |
| 1894 | -12.568 | -14.401 |
| 1895 | -15.118 | -13.221 |
| 1896 | -16.872 | -13.981 |
| 1897 | -16.136 | -13.461 |
| 1898 | -11.946 | -12.521 |
| 1899 | -10.267 | -11.771 |
| 1900 | -14.705 | -12.311 |
| 1901 | -17.569 | -12.351 |
| 1902 | -17.622 | -11.891 |
| 1903 | -8.113 | -11.091 |
| 1904 | -13.587 | -12.121 |
| 1905 | -14.526 | -12.671 |
| 1906 | -12.638 | -11.991 |
| 1907 | -14.865 | -12.131 |
| 1908 | -15.782 | -12.381 |
| 1909 | -11.197 | -11.931 |
| 1910 | -10.079 | -11.941 |
| 1911 | -10.775 | -11.111 |
| 1912 | -6.77 | -11.421 |
| 1913 | -9.333 | -11.241 |
| 1914 | -7.487 | -10.611 |
| 1915 | -11.922 | -9.821 |
| 1916 | -7.251 | -10.011 |
| 1917 | -12.218 | -10.461 |
| 1918 | -11.897 | -10.621 |
| 1919 | -13.894 | -10.461 |
| 1920 | -11.37 | -10.331 |
| 1921 | -10.168 | -10.121 |
| 1922 | -10.829 | -10.211 |
| 1923 | -9.568 | -10.091 |
| 1924 | -9.678 | -10.821 |
| 1925 | -6.084 | -10.621 |
| 1926 | -7.224 | -9.971 |
| 1927 | -6.988 | -10.081 |
| 1928 | -6.958 | -10.471 |
| 1929 | -10.688 | -10.331 |
| 1930 | -7.028 | -9.931 |
| 1931 | -6.2 | -9.971 |
| 1932 | -6.019 | -9.401 |
| 1933 | -11.112 | -8.971 |
| 1934 | -8.506 | -9.511 |
| 1935 | -5.955 | -8.951 |
| 1936 | -5.071 | -9.341 |
| 1937 | -6.529 | -8.771 |
| 1938 | -4.905 | -8.511 |
| 1939 | -8.701 | -7.991 |
| 1940 | -7.941 | -8.521 |
| 1941 | -11.207 | -7.301 |
| 1942 | -9.281 | -7.301 |
| 1943 | -3.999 | -7.301 |
| 1944 | -4.348 | -7.941 |
| 1945 | -3.463 | -7.661 |
| 1946 | -3.902 | -6.911 |
| 1947 | -10.025 | -6.601 |
| 1948 | -2.014 | -6.121 |
| 1949 | -2.017 | -6.251 |
| 1950 | -2.408 | -6.031 |
| 1951 | -3.733 | -5.081 |
| 1952 | -3.024 | -5.341 |
| 1953 | -4.851 | -4.901 |
| 1954 | -3.763 | -5.191 |
| 1955 | -2.521 | -5.101 |
| 1956 | -7.444 | -5.611 |
| 1957 | -4.07 | -4.271 |
| 1958 | -3.842 | -4.131 |
| 1959 | -6.409 | -4.101 |
| 1960 | -3.761 | -3.731 |
| 1961 | 1.308 | -3.111 |
| 1962 | -3.417 | -3.631 |
| 1963 | -6.673 | -3.791 |
| 1964 | -5.935 | -4.581 |
| 1965 | -2.814 | -3.461 |
| 1966 | -0.045 | -4.001 |
| 1967 | 2.506 | -3.861 |
| 1968 | -2.147 | -3.781 |
| 1969 | -3.439 | -3.101 |
| 1970 | -1.976 | -3.291 |
| 1971 | -4.246 | -2.771 |
| 1972 | -6.845 | -1.861 |
| 1973 | -3.551 | -2.461 |
| 1974 | -2.087 | -1.271 |
| 1975 | -4.537 | -1.431 |
| 1976 | -6.913 | -1.531 |
| 1977 | -2.303 | -1.701 |
| 1978 | -3.966 | -1.061 |
| 1979 | -2.797 | -1.551 |
| 1980 | -1.702 | -0.951 |
| 1981 | 1.885 | 0.289 |
| 1982 | 1.251 | -0.291 |
| 1983 | 3.646 | 0.549 |
| 1984 | -2.487 | 0.459 |
| 1985 | -0.755 | -0.571 |
| 1986 | -1.633 | -0.511 |
| 1987 | -1.571 | -0.451 |
| 1988 | 4.439 | 0.019 |
| 1989 | 3.627 | 0.469 |
| 1990 | 4.961 | 0.609 |
| 1991 | -4.042 | 0.919 |
| 1992 | -0.735 | 1.199 |
| 1993 | -1.303 | 0.749 |
| 1994 | 2.702 | 1.089 |
| 1995 | 2.388 | 1.609 |
| 1996 | -5.454 | 1.979 |
| 1997 | -0.157 | 2.799 |
| 1998 | 4.492 | 2.039 |
| 1999 | 4.796 | 2.709 |
| 2000 | 4.847 | 2.799 |
| 2001 | 4.238 | 3.249 |
| 2002 | 4.621 | 3.149 |
| 2003 | 4.241 | 4.049 |
| 2004 | 5.283 | 3.989 |
| 2005 | 3.117 | 3.949 |
| 2006 | 4.61 | 4.099 |
| 2007 | 7.858 | 4.449 |
| 2008 | 6.503 | 5.439 |
| 2009 | 3.968 | 6.089 |
| 2010 | ||
| 2011 |