Question: when did they stop using cabooses on trains
[{'answer': 'the 1980s', 'provenance': [{'wikipedia_id': '329956', 'title': 'Caboose', 'start_paragraph_id': 4, 'start_character': 59, 'end_paragraph_id': 4, 'end_character': 68, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '329956', 'title': 'Caboose', 'start_paragraph_id': 4, 'start_character': 0, 'end_paragraph_id': 4, 'end_character': 450, 'bleu_score': 0.935942197527824, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 6853519067598237129}, 'section': 'Section::::Abstract.'}]}]