Question: when did the most recent el niño occur
[{'answer': '2014 -- 16'}, {'provenance': [{'wikipedia_id': '10531', 'title': 'El Niño', 'start_paragraph_id': 11, 'start_character': 0, 'end_paragraph_id': 11, 'end_character': 247, 'bleu_score': 0.581430736968219, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 13024691637441939040}, 'section': 'Section::::Occurrences.\n'}]}]