Question: when did the steel mills closed in youngstown ohio
[{'answer': 'September 19 , 1977', 'provenance': [{'wikipedia_id': '30076877', 'title': 'Economy of Youngstown, Ohio', 'start_paragraph_id': 10, 'start_character': 1106, 'end_paragraph_id': 10, 'end_character': 1125, 'bleu_score': 1.0, 'section': 'Section::::Black Monday.\n'}]}, {'provenance': [{'wikipedia_id': '30076877', 'title': 'Economy of Youngstown, Ohio', 'start_paragraph_id': 11, 'start_character': 0, 'end_paragraph_id': 11, 'end_character': 1426, 'bleu_score': 0.8835381915840911, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 4317420876389649788}, 'section': 'Section::::Black Monday.\n'}]}, {'provenance': [{'wikipedia_id': '30076877', 'title': 'Economy of Youngstown, Ohio', 'start_paragraph_id': 2, 'start_character': 0, 'end_paragraph_id': 2, 'end_character': 666, 'bleu_score': 0.9575690457118191, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 4317420876389649788}, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '30076877', 'title': 'Economy of Youngstown, Ohio', 'start_paragraph_id': 0, 'start_character': 0, 'end_paragraph_id': 0, 'end_character': 0, 'bleu_score': 1.0, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 4317420876389649788}, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '30076877', 'title': 'Economy of Youngstown, Ohio', 'section': 'Section::::Black Monday.\n', 'start_paragraph_id': 10, 'end_paragraph_id': 10, 'meta': {'evidence_span': ['On September 19, 1977, it was announced a large portion of Youngstown Sheet and Tube would be closing.', 'Between the 1920s and 1960s, the city was known as an important industrial hub that featured the massive furnaces and foundries of such companies as Republic Steel and U.S. Steel. At the same time, Youngstown never became economically diversified, as did larger industrial cities such as Chicago, Pittsburgh, Akron, or Cleveland. Though population levels remained flat for a few more decades, population had not grown since the Great Depression, though General Motors had opened Lordstown Assembly in 1966 to help offset some losses. Hence, when economic changes forced the closure of plants throughout the 1970s, the city was left with few substantial economic alternatives. The 1969 corporate merger between the Youngstown Sheet and Tube Company and the New Orleans-based Lykes Corporation proved to be a turning point in the demise of the local steel industry.', 'On September 19, 1977, it was announced a large portion of Youngstown Sheet and Tube would be closing.']}}]}]