Question: which age group of population indicates the largest working population
[{'answer': '15 -- 64'}, {'provenance': [{'wikipedia_id': '989011', 'title': 'Population pyramid', 'start_paragraph_id': 5, 'start_character': 0, 'end_paragraph_id': 5, 'end_character': 1919, 'bleu_score': 0.9639105294588691, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 13957940706411941077}, 'section': 'Section::::Structure.\n'}]}]