1911 Census of England and Wales, General Report with Appendices, Table 102 : " Persons born in London and enumerated in certain Counties in England and Wales".

Where enumerated. Proportion per 100,000 natives of London enumerated in England and Wales.
1851. 1861. 1871. 1881. 1891. 1901. 1911.
London 86,281 84,475 82,487 80,422 76,949 73,009 67,204
Middlesex (extra-metro-
  politan)
1,350 1,622 2,185 3,176 4,718 5,842 7,791
Essex 885 1,306 1,788 2,790 4,263 6,330 7,674
Surrey (extra-metropoli-
  tan)
1,103 }3,035{ 2,221 2,227 2,460 2,760 3,756
Kent (extra-metropolitan) 1,378 1,620 1,829 1,937 2,239 2,542
Sussex 823 933 978 1,139 1,294 1,314 1,432
Hampshire 678 908 916 853 1,035 1,120 1,404