Question: when was national insurance introduced in the uk
[{'answer': '1911', 'provenance': [{'wikipedia_id': '316844', 'title': 'National Insurance', 'start_paragraph_id': 2, 'start_character': 54, 'end_paragraph_id': 2, 'end_character': 58, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '316844', 'title': 'National Insurance', 'start_paragraph_id': 2, 'start_character': 0, 'end_paragraph_id': 2, 'end_character': 173, 'bleu_score': 0.929712191543383, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 392340571969143578}, 'section': 'Section::::Abstract.'}]}]