Question: when did the nhl expand from 6 teams
[{'answer': '1963', 'provenance': [{'wikipedia_id': '18599942', 'title': 'History of the National Hockey League (1967–1992)', 'start_paragraph_id': 6, 'start_character': 70, 'end_paragraph_id': 6, 'end_character': 74, 'bleu_score': 1.0, 'section': 'Section::::Background.\n'}]}, {'provenance': [{'wikipedia_id': '18599942', 'title': 'History of the National Hockey League (1967–1992)', 'start_paragraph_id': 6, 'start_character': 0, 'end_paragraph_id': 6, 'end_character': 912, 'bleu_score': 0.9638487952440571, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 12245027378346857732}, 'section': 'Section::::Background.\n'}]}]