What is the lowest rank?
{'header': ['Rank', 'Couple', 'Judges', 'Public', 'Total', 'Vote percentage', 'Result'], 'page_title': '', 'page_id': '', 'types': ['real', 'text', 'real', 'real', 'real', 'text', 'text'], 'id': '1-19744915-15', 'section_title': '', 'caption': '', 'rows': [['1', 'Ray and Maria', '7', '7', '14', '42.658%', 'Safe'], ['2', 'Michael and Melanie', '5', '5', '10', '12.863%', 'Safe'], ['3', 'Ellery and Frankie', '6', '4', '10', '9.515%', 'Safe'], ['4', 'Todd and Susie', '1', '6', '7', '18.155%', 'Safe'], ['5', 'Jeremy and Darya', '5', '1', '6', '3.233%', 'Safe'], ['6', 'Donal and Florentine', '2', '3', '5', '7.691%', 'Bottom two']], 'name': 'table_19744915_15'}