CHART XXIII.
CHART XXIV.
CHART XXV.
CHART XXVI.
The first fact gained from a study of the 1920 occupational case rate is that just as was the case in age incidence there is less variation between the highest and the lowest than in 1918–19. While in the first epidemic the highest occupational rate was five times the lowest, in the second it was only twice the lowest (Chart XXV). But at the extremes of the two charts we see some tendency to an inversion of the order. In 1918–19 those occupied in “retail sales” outdoors showed a low incidence, while in 1920 they were the highest. So also, the incidence in the school group changed from highest in 1918 to lowest in 1920. The incidence in infants increased; that in the office workers decreased. No general conclusions are warranted from these results.