The Standard Time Act was enacted in 1918 by President Woodrow Wilson, placing the four time zones adopted by U.S. and Canadian railroads in 1883 under federal oversight, and began the concept of “saving” time by shifting the clock to add an extra hour of sunlight to each day to save on fuel costs during World War I. After the war the federal government shifted the responsibility back to states, which could opt to continue the practice or drop it. The feds re-adopted the practice for the entire nation two other times in history for energy savings, during World War II and during the oil embargo crisis from 1973-75.