1911 Census of England and Wales, General Report with Appendices, Table 121: " Proportion of the Insane per Million living in each Age-Group, 1871-1911".

Ages. Insanity Rate per million living. Increase or Decrease per cent. of
Insanity Rate.
1871. 1881. 1891. 1901. 1911. 1871—81. 1881—91. 1891—
1901.
1901—
1911.
All Ages 3,039 3,253 3,358 4,078 4,491 7.0 3.2 21.4 10.1
Under l5 years 583 581 509 629 823 -0.3 -12.4 23.6 30.8
15—25 2,298 2,161 2,002 2,388 2,748 -6.0 -7.4 19.3 15.1
25—45 4,498 4,789 4,756 5,263 5,298 6.5 -0.7 10.7 0.7
45-65 6,158 7,205 7,831 9,087 9,504 17.0 8.7 16.0 4.6
65 and upwards 6,950 8,000 8,612 11,922 11,925 15.1 7.7 38.4 0.0