Question: when did the motion picture rating system start
[{'answer': 'November 1 , 1968', 'provenance': [{'wikipedia_id': '75890', 'title': 'Motion Picture Association of America film rating system', 'start_paragraph_id': 20, 'start_character': 3, 'end_paragraph_id': 20, 'end_character': 20, 'bleu_score': 1.0, 'section': 'Section::::History.:Replacement of the Hays Code.\n'}]}, {'provenance': [{'wikipedia_id': '75890', 'title': 'Motion Picture Association of America film rating system', 'start_paragraph_id': 19, 'start_character': 0, 'end_paragraph_id': 19, 'end_character': 1032, 'bleu_score': 0.520779369153752, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 11546088621110644833}, 'section': 'Section::::History.:Replacement of the Hays Code.\n'}]}]