I want to know the answer to the following question:
What year did the United States finally adopt Daylight Saving Time?
All the background I'm provided with is that "After Germany led the way with starting DST (German: Sommerzeit) during World War I on 30 April 1916 together with its allies to alleviate hardships from wartime coal shortages and air raid blackouts, the political equation changed in other countries; the United Kingdom used DST first on 21 May 1916.". Is that enough to answer the question?
Answer: no