Question: how many planet fitnesses are there in the united states
[{'answer': '1,600'}, {'provenance': [{'wikipedia_id': '6898340', 'title': 'Planet Fitness', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 544, 'bleu_score': 0.886473199858392, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 3619666264801393958}, 'section': 'Section::::Abstract.'}]}]