Question: what percent of the world's population is america
[{'answer': '4.4 percent', 'provenance': [{'wikipedia_id': '17218450', 'title': 'United States incarceration rate', 'start_paragraph_id': 40, 'start_character': 539, 'end_paragraph_id': 40, 'end_character': 549, 'bleu_score': 1.0, 'section': 'Section::::Causes.:Prison privatization.\n'}]}]