Question: when was kwanzaa first celebrated in the united states
[{'answer': '1966 -- 67'}, {'provenance': [{'wikipedia_id': '17422', 'title': 'Kwanzaa', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 399, 'bleu_score': 0.905470351340632, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 17787332217799997038}, 'section': 'Section::::Abstract.'}]}]