Question: when did the half crown go out of circulation
[{'answer': '1967', 'provenance': [{'wikipedia_id': '527167', 'title': 'Half crown (British coin)', 'start_paragraph_id': 1, 'start_character': 367, 'end_paragraph_id': 1, 'end_character': 371, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '527167', 'title': 'Half crown (British coin)', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 371, 'bleu_score': 0.9712154609069981, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 4980061016725001417}, 'section': 'Section::::Abstract.'}]}]