Question: when did the bank of england become independent
[{'answer': '1998', 'provenance': [{'wikipedia_id': '4484', 'title': 'Bank of England', 'start_paragraph_id': 2, 'start_character': 54, 'end_paragraph_id': 2, 'end_character': 58, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '4484', 'title': 'Bank of England', 'start_paragraph_id': 2, 'start_character': 0, 'end_paragraph_id': 2, 'end_character': 176, 'bleu_score': 0.697756759594737, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 4900960180158096344}, 'section': 'Section::::Abstract.'}]}]