Question

between which two years was the change in the number of influenza deaths most significant

Answer 1

Explanation:

In between 1917 and 1918 the change in the number of influenza deaths were most significant. Moreover, during that time the influenza virus claim the highest number of victims in US. It was the period of in between late September and early December of 1918. It was the time when the deaths were recorded on a massive scale in United States.