Question: when did equal pay for equal work begin
[{'answer': '1963', 'provenance': [{'wikipedia_id': '1108449', 'title': 'Equal pay for equal work', 'start_paragraph_id': 1, 'start_character': 477, 'end_paragraph_id': 1, 'end_character': 481, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '1108449', 'title': 'Equal pay for equal work', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 606, 'bleu_score': 0.9325152759335561, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 11823453588784680621}, 'section': 'Section::::Abstract.'}]}]