From "Influenza and pneumonia (All forms)" p. 28:
"In the later part of 1918 a pandemic of influenza swept over the country and did not fully spend its force until well into 1919....
"In the registration area (exclusive of Hawaii) the 189,326 deaths from influenza and pneumonia (all forms) in 1919 correspond to a rate of 222.4 per 100,000 population as against 479,038 deaths in 1918, with a rate of 588.7. Fully 79.8 per cent of the mortality from these causes in 1918 occurred in the last four months of the year, and as the pandemic continued into 1919, fully 83.2 per cent of the mortality from these causes in 1919 occured in the first six months of the year...."
Digital facsimile from the Hathi Trust at this link.