Question: when did we start using daylight savings time in the united states
[{'answer': '1918', 'provenance': [{'wikipedia_id': '480675', 'title': 'History of time in the United States', 'start_paragraph_id': 2, 'start_character': 206, 'end_paragraph_id': 2, 'end_character': 210, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '480675', 'title': 'History of time in the United States', 'start_paragraph_id': 2, 'start_character': 0, 'end_paragraph_id': 2, 'end_character': 345, 'bleu_score': 0.9657992495762461, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 6062253612416200379}, 'section': 'Section::::Abstract.'}]}]