1921 Census of England and Wales, General Report with Appendices, Table 4 : " Revised Intercensal Estimates of Population of England and Wales, 1911-1920".

As at the Midlde of the Year. Persons. Males. Females.
1911 36,136 17,471 18,665
1912 36,327 17,571 18,756
1913 36,574 17,687 18,887
1914 36,967 17,885 19,082
  A B A B  
1915 35,284 37,432 16,003 18,151 19,281
1916 34,642 37,592 15,222 18,172 19,420
1917 34,197 37,680 14,661 18,144 19,536
1918 34,024 37,636 14,433 18,045 19,591
1919 35,427 37,520 15,868 17,961 19,559
1920 37,247 37,756 17,582 18,091 19,665

NOTE.—For the years 1911-14 the figures represent the total population within the country.
For the years 1915-20 the figures shown under columns A refer to civilians only, and under columns B to civilians plus all non-civilians belonging to England and Wales whether the latter were within the country or not.