Chart description: just gone  1940 there was the most personel  and at the end of 1900 it  only was slighty lower in 2020 it is lowest.

Chart data: Year Number of personnel Dec 31, 1899 416.4 Dec 31, 1900 539.8 Dec 31, 1901 520.2 Dec 31, 1902 451.8 Dec 31, 1903 418.3 Dec 31, 1904 401.1 Dec 31, 1905 392.1 Dec 31, 1906 376.5 Dec 31, 1907 379.3 Dec 31, 1908 381.4 Dec 31, 1909 383.7 Dec 31, 1910 388.3 Dec 31, 1911 389.8 Dec 31, 1912 393.3 Dec 31, 1913 1478.4 Dec 31, 1914 2825.8 Dec 31, 1915 3834.8 Dec 31, 1916 4333 Dec 31, 1917 4583.3 Dec 31, 1918 1604.7 Dec 31, 1919 597.7 Dec 31, 1920 438.5 Dec 31, 1921 368 Dec 31, 1922 334.7 Dec 31, 1923 339.3 Dec 31, 1924 342.3 Dec 31, 1925 341 Dec 31, 1926 339.3 Dec 31, 1927 330.7 Dec 31, 1928 325.6 Dec 31, 1929 317.3 Dec 31, 1930 319.1 Dec 31, 1931 316.8 Dec 31, 1932 316.4 Dec 31, 1933 317.4 Dec 31, 1934 320.8 Dec 31, 1935 339.3 Dec 31, 1936 352.4 Dec 31, 1937 384.8 Dec 31, 1938 1068.85 Dec 31, 1939 1812.6 Dec 31, 1940 3285.4 Dec 31, 1941 3880.8 Dec 31, 1942 4452.8 Dec 31, 1943 4691.1 Dec 31, 1944 4906.4 Dec 31, 1945 1937.8 Dec 31, 1946 1255 Dec 31, 1947 830 Dec 31, 1948 759.5 Dec 31, 1949 696.4 Dec 31, 1950 823.8 Dec 31, 1951 871.7 Dec 31, 1952 868 Dec 31, 1953 840.1 Dec 31, 1954 804.7 Dec 31, 1955 762.3 Dec 31, 1956 703.9 Dec 31, 1957 615.5 Dec 31, 1958 566.5 Dec 31, 1959 521.1 Dec 31, 1960 457.5 Dec 31, 1961 434 Dec 31, 1962 417.5 Dec 31, 1963 416.7 Dec 31, 1964 414.6 Dec 31, 1965 409.5 Dec 31, 1966 406.6 Dec 31, 1967 395.8 Dec 31, 1968 383 Dec 31, 1969 373 Dec 31, 1970 368 Dec 31, 1971 371.4 Dec 31, 1972 367 Dec 31, 1973 349.3 Dec 31, 1974 338.4 Dec 31, 1975 336.6 Dec 31, 1976 330.5 Dec 31, 1977 320.7 Dec 31, 1978 315 Dec 31, 1979 320.6 Dec 31, 1980 333.8 Dec 31, 1981 327.6 Dec 31, 1982 320.6 Dec 31, 1983 325.9 Dec 31, 1984 326.2 Dec 31, 1985 322.5 Dec 31, 1986 319.8 Dec 31, 1987 316.9 Dec 31, 1988 311.6 Dec 31, 1989 305.8 Dec 31, 1990 298.1 Dec 31, 1991 293.4 Dec 31, 1992 274.8 Dec 31, 1993 254.5 Dec 31, 1994 233.3 Dec 31, 1995 221.9 Dec 31, 1996 210.8 Dec 31, 1997 210.1 Dec 31, 1998 208.6 Dec 31, 1999 207.6 Dec 31, 2000 205.6 Dec 31, 2001 204.7 Dec 31, 2002 206.9 Dec 31, 2003 207 Dec 31, 2004 201.1 Dec 31, 2005 195.9 Dec 31, 2006 190.4 Dec 31, 2007 187.1 Dec 31, 2008 188.4 Dec 31, 2009 191.7 Dec 31, 2010 186.4 Dec 31, 2011 179.8 Dec 31, 2012 170.71 Dec 31, 2013 159.63 Dec 31, 2014 153.72 Dec 31, 2015 151 Dec 31, 2016 149.37 Dec 31, 2017 146.56 Dec 31, 2018 144.43 Dec 31, 2019 145.32

Vega-Lite specification:
{"config": {"background": "#fff", "area": {"fill": "#4572a7"}, "line": {"stroke": "#4572a7", "strokeWidth": 2}, "rect": {"fill": "#4572a7"}, "bar": {"fill": "#4572a7"}, "point": {"color": "#4572a7", "strokeWidth": 1.5, "size": 50}, "axis": {"bandPosition": 0.5, "grid": true, "gridColor": "#000000", "gridOpacity": 1, "gridWidth": 0.5, "labelPadding": 10, "tickSize": 5, "tickWidth": 0.5}, "axisBand": {"grid": false, "tickExtra": true}, "legend": {"labelBaseline": "middle", "labelFontSize": 11, "symbolSize": 50, "symbolType": "square"}, "range": {"category": ["#4572a7", "#aa4643", "#8aa453", "#71598e", "#4598ae", "#d98445", "#94aace", "#d09393", "#b9cc98", "#a99cbc"]}}, "data": {"url": "data/1997.tsv"}, "mark": "area", "encoding": {"color": {"value": "#4572a7"}, "x": {"type": "temporal", "axis": {}, "bin": false, "field": "Year"}, "y": {"type": "quantitative", "axis": {"labelAngle": 45, "title": "Number of personnel"}, "field": "Number of personnel"}}, "title": ["Number of personnel in the armed forces", "of the United Kingdom (UK) from 1900 to 2020", "(in 1,000s)"], "$schema": "https://vega.github.io/schema/vega-lite/v4.8.1.json"}