Question: what does the na mean after a bank name
[{'answer': 'National Association', 'provenance': [{'wikipedia_id': '603356', 'title': 'National bank', 'start_paragraph_id': 65, 'start_character': 330, 'end_paragraph_id': 65, 'end_character': 350, 'bleu_score': 1.0, 'section': 'Section::::By country.:United States of America.\n'}]}, {'provenance': [{'wikipedia_id': '603356', 'title': 'National bank', 'start_paragraph_id': 65, 'start_character': 0, 'end_paragraph_id': 65, 'end_character': 730, 'bleu_score': 0.9581238714434541, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 17107050581477143139}, 'section': 'Section::::By country.:United States of America.\n'}]}]