Question: what was the highest oil price per barrel
[{'answer': 'US $147.27', 'provenance': [{'wikipedia_id': '5137675', 'title': 'Price of oil', 'start_paragraph_id': 10, 'start_character': 127, 'end_paragraph_id': 10, 'end_character': 135, 'bleu_score': 1.0, 'section': 'Section::::History.:Price history in the 21st century.\n'}]}, {'provenance': [{'wikipedia_id': '5137675', 'title': 'Price of oil', 'start_paragraph_id': 10, 'start_character': 0, 'end_paragraph_id': 10, 'end_character': 1295, 'bleu_score': 0.842948860652121, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 11569543294959643781}, 'section': 'Section::::History.:Price history in the 21st century.\n'}]}]