Question: when did midwest express go out of business
[{'answer': 'in late 2011', 'provenance': [{'wikipedia_id': '143193', 'title': 'Midwest Airlines', 'start_paragraph_id': 1, 'start_character': 384, 'end_paragraph_id': 1, 'end_character': 396, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '143193', 'title': 'Midwest Airlines', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 396, 'bleu_score': 0.906944319610487, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 11141997595788168694}, 'section': 'Section::::Abstract.'}]}]