Question: when was the last time the us hosted the world cup
[{'answer': '1994', 'provenance': [{'wikipedia_id': '4743361', 'title': 'FIFA World Cup hosts', 'start_paragraph_id': 110, 'start_character': 11, 'end_paragraph_id': 110, 'end_character': 15, 'bleu_score': 1.0, 'section': 'Section::::1990 FIFA World Cup.\n'}]}]