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Hydrionis connects global water data, science, infrastructure and history into one evidence-based intelligence platform. Every number carries its source, its method and its licence — and where a value is not held, Hydrionis says so instead of estimating one.
View the data behind this chart
Records long enough to mean something
Hydrionis holds English rainfall from 1836 and groundwater levels from the same decade, ingested directly from their publishers. A record this long is what makes it possible to say whether a dry year is unusual, rather than only that it was dry — the driest year here is 1921, at 36% below the 1991–2020 average.
- Annual rainfall against the long-term normal
- 10-year mean
A shaded drought does not always coincide with a low annual total: droughts are made by the timing of rainfall and by what was already in the ground, not by the calendar-year sum.
View the data behind this chart
| Period | Annual rainfall against the long-term normal (%) | 10-year mean (%) |
|---|---|---|
| 1836 | 1.83 | — |
| 1837 | -14.2 | — |
| 1838 | -12.6 | — |
| 1839 | 5.69 | — |
| 1840 | -20.9 | — |
| 1841 | 11.2 | -8.24 |
| 1842 | -16.3 | -8.93 |
| 1843 | -4.28 | -8.95 |
| 1844 | -25.0 | -6.09 |
| 1845 | -7.78 | -7.67 |
| 1846 | -5.11 | -7.50 |
| 1847 | -14.4 | -10.4 |
| 1848 | 16.0 | -6.67 |
| 1849 | -10.0 | -7.26 |
| 1850 | -19.2 | -7.54 |
| 1851 | -18.1 | -9.18 |
| 1852 | 21.3 | -9.75 |
| 1853 | -10.2 | -9.85 |
| 1854 | -27.8 | -13.9 |
| 1855 | -24.1 | -13.6 |
| 1856 | -10.9 | -10.6 |
| 1857 | -15.4 | -10.1 |
| 1858 | -25.0 | -12.7 |
| 1859 | -6.33 | -12.8 |
| 1860 | 10.7 | -12.8 |
| 1861 | -13.5 | -11.0 |
| 1862 | -4.83 | -9.11 |
| 1863 | -11.3 | -8.43 |
| 1864 | -27.7 | -6.52 |
| 1865 | -5.62 | -6.24 |
| 1866 | 7.78 | -9.83 |
| 1867 | -8.60 | -9.56 |
| 1868 | -5.79 | -5.79 |
| 1869 | -3.59 | -6.37 |
| 1870 | -25.1 | -5.02 |
| 1871 | -10.7 | -3.95 |
| 1872 | 32.8 | -3.99 |
| 1873 | -17.1 | -1.55 |
| 1874 | -14.2 | -0.964 |
| 1875 | 5.05 | -0.655 |
| 1876 | 7.33 | 2.27 |
| 1877 | 15.9 | 3.32 |
| 1878 | 0.046 | 1.72 |
| 1879 | -0.494 | 3.44 |
| 1880 | 4.11 | 2.86 |
| 1881 | -0.207 | 1.62 |
| 1882 | 16.8 | 1.39 |
| 1883 | 0.149 | -3.34 |
| 1884 | -20.0 | -4.36 |
| 1885 | -7.38 | -5.70 |
| 1886 | 5.03 | -7.77 |
| 1887 | -31.4 | -7.41 |
| 1888 | -10.1 | -10.4 |
| 1889 | -13.9 | -12.7 |
| 1890 | -16.6 | -10.7 |
| 1891 | 3.40 | -11.1 |
| 1892 | -13.1 | -13.1 |
| 1893 | -22.7 | -10.6 |
| 1894 | -0.253 | -11.6 |
| 1895 | -11.8 | -11.6 |
| 1896 | -14.1 | -9.89 |
| 1897 | -7.21 | -12.3 |
| 1898 | -20.3 | -13.2 |
| 1899 | -13.1 | -8.93 |
| 1900 | 0.218 | -10.7 |
| 1901 | -20.3 | -11.7 |
| 1902 | -22.4 | -11.0 |
| 1903 | 19.9 | -11.0 |
| 1904 | -17.6 | -10.7 |
| 1905 | -22.4 | -9.68 |
| 1906 | -7.26 | -9.36 |
| 1907 | -6.85 | -8.60 |
| 1908 | -17.6 | -4.84 |
| 1909 | -2.54 | -7.98 |
| 1910 | 3.38 | -6.24 |
| 1911 | -12.6 | -3.83 |
| 1912 | 15.2 | -2.46 |
| 1913 | -11.5 | -2.76 |
| 1914 | -0.207 | -1.15 |
| 1915 | 1.69 | -1.29 |
| 1916 | 6.51 | -1.93 |
| 1917 | -9.89 | -4.24 |
| 1918 | -1.46 | -6.08 |
| 1919 | -3.97 | -4.66 |
| 1920 | -3.02 | -3.64 |
| 1921 | -35.7 | -4.08 |
| 1922 | -3.18 | -5.39 |
| 1923 | 2.67 | -3.11 |
| 1924 | 9.92 | -2.49 |
| 1925 | -2.64 | -2.96 |
| 1926 | -6.62 | -1.93 |
| 1927 | 12.9 | 1.77 |
| 1928 | 4.72 | 1.56 |
| 1929 | -8.63 | -1.23 |
| 1930 | 7.30 | -3.50 |
| 1931 | 1.25 | -2.86 |
| 1932 | -5.24 | -2.21 |
| 1933 | -25.2 | -3.44 |
| 1934 | -12.8 | -4.68 |
| 1935 | 3.74 | -3.33 |
| 1936 | -0.138 | -4.76 |
| 1937 | 0.575 | -6.03 |
| 1938 | -7.62 | -6.86 |
| 1939 | 4.89 | -5.72 |
| 1940 | -7.01 | -5.09 |
| 1941 | -11.5 | -6.92 |
| 1942 | -13.5 | -5.93 |
| 1943 | -13.8 | -7.63 |
| 1944 | -6.48 | -7.00 |
| 1945 | -14.6 | -9.31 |
| 1946 | 9.74 | -8.18 |
| 1947 | -16.3 | -5.69 |
| 1948 | -1.36 | -5.19 |
| 1949 | -18.2 | -6.01 |
| 1950 | 4.34 | -4.04 |
| 1951 | 13.4 | -4.61 |
| 1952 | -8.55 | -6.58 |
| 1953 | -22.1 | -5.62 |
| 1954 | 13.2 | -4.72 |
| 1955 | -20.2 | -4.48 |
| 1956 | -10.0 | -2.70 |
| 1957 | -6.75 | -4.80 |
| 1958 | 7.64 | -5.55 |
| 1959 | -15.8 | -4.24 |
| 1960 | 22.1 | -8.05 |
| 1961 | -7.60 | -5.47 |
| 1962 | -16.0 | -3.55 |
| 1963 | -9.01 | -2.43 |
| 1964 | -24.9 | -2.81 |
| 1965 | 5.61 | -1.79 |
| 1966 | 9.13 | -4.42 |
| 1967 | 4.47 | -5.25 |
| 1968 | 3.83 | -4.69 |
| 1969 | -5.54 | -6.13 |
| 1970 | -4.25 | -3.06 |
| 1971 | -15.8 | -5.71 |
| 1972 | -10.4 | -8.21 |
| 1973 | -23.4 | -8.93 |
| 1974 | 5.74 | -9.91 |
| 1975 | -20.9 | -8.95 |
| 1976 | -15.9 | -8.34 |
| 1977 | -2.66 | -6.28 |
| 1978 | -6.03 | -5.14 |
| 1979 | 4.11 | -3.60 |
| 1980 | 1.78 | -4.59 |
| 1981 | 4.82 | -3.20 |
| 1982 | 0.943 | -1.20 |
| 1983 | -7.98 | -1.21 |
| 1984 | -4.13 | -0.923 |
| 1985 | -6.98 | -2.87 |
| 1986 | 4.07 | -4.37 |
| 1987 | -2.68 | -6.58 |
| 1988 | -3.20 | -6.63 |
| 1989 | -15.3 | -5.44 |
| 1990 | -13.2 | -4.53 |
| 1991 | -17.3 | -5.19 |
| 1992 | 0.437 | -7.81 |
| 1993 | 3.90 | -8.54 |
| 1994 | 5.03 | -7.11 |
| 1995 | -13.6 | -4.82 |
| 1996 | -22.2 | -0.754 |
| 1997 | -9.95 | 0.895 |
| 1998 | 11.1 | 2.42 |
| 1999 | 7.55 | -0.217 |
| 2000 | 27.5 | -0.493 |
| 2001 | -0.839 | -0.566 |
| 2002 | 15.7 | 1.36 |
| 2003 | -22.5 | 3.08 |
| 2004 | 2.28 | 3.25 |
| 2005 | -14.3 | 2.55 |
| 2006 | -2.93 | -1.85 |
| 2007 | 7.25 | -3.57 |
| 2008 | 12.8 | -2.20 |
| 2009 | 0.529 | -0.608 |
| 2010 | -16.5 | 0.462 |
| 2011 | -18.1 | 1.86 |
| 2012 | 29.4 | 1.61 |
| 2013 | -6.55 | 0.370 |
| 2014 | 13.0 | -1.77 |
| 2015 | -0.368 | -0.566 |
| 2016 | -5.37 | 2.45 |
| 2017 | -5.16 | 4.34 |
| 2018 | -8.63 | 0.354 |
| 2019 | 12.6 | 3.32 |
| 2020 | 13.7 | 3.93 |
| 2021 | 0.851 | 3.14 |
| 2022 | -10.5 | — |
| 2023 | 23.1 | — |
| 2024 | 19.1 | — |
| 2025 | -8.31 | — |
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