Digital facsimile from the Hathi Trust at this link.

From Causes of Death, p. 27:

"Influenza and pneumonia (All forms).

"In 1918 the registration area (exclusive of Hawaii) 477,467 deaths wee assigned to influenza and pneumonia (all forms). In the latter part of that year a pandemic on influenza swept over the country and did not fully spend its force until well into 1919....

"The 477,467 deaths from influenza and penumonia (all forms) in 1918 correspond to a rate of 583.2 per 100,000 population as against 125,795 in 1917 and a rate of 167, which till 1918, was the highest rare from these causes for any year since 1910. Fully 79.8 per cent of the mortality from these causes in 1918 occurred in the last four months of the year...."

Digital facsimile from Google Books at this link.

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.

Chapter B, "Vital statistics and health and medical care."  Digital facsimile from the Internet Archive at this link; from the U. S. Census Bureau at this link.

Digital facsimile from Google Books at this link.