Question: when did the hartford civic center roof collapse
[{'answer': 'January 18 , 1978', 'provenance': [{'wikipedia_id': '1754468', 'title': 'XL Center', 'start_paragraph_id': 8, 'start_character': 154, 'end_paragraph_id': 8, 'end_character': 171, 'bleu_score': 1.0, 'section': 'Section::::Hartford Civic Center.:Early history and roof collapse.\n'}]}, {'provenance': [{'wikipedia_id': '1754468', 'title': 'XL Center', 'start_paragraph_id': 8, 'start_character': 0, 'end_paragraph_id': 8, 'end_character': 460, 'bleu_score': 0.5595738614855621, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 1505166966044150737}, 'section': 'Section::::Hartford Civic Center.:Early history and roof collapse.\n'}]}]