The assination of archduke francis ferdinand
Answer: it dropped almost by 10%
Explanation:
America's involvement in World War II had a significant impact on the economy and workforce of the United States. Our involvement in the war soon changed that rate. American factories were retooled to produce goods to support the war effort and almost overnight the unemployment rate dropped to around 10%.
I don't have the proper answer and you might have to do research but America did gain much from the war such as Cuba, The Philipines, and Guam.