Head to Head HRT driver comparison for 2011 season.
[{'label': 'Vitantonio Liuzzi', 'data': [22, 23, 24, 24, 23, 20, 20, 20, 20, 20, 21, 23, 23, 23, 23, None, 23, 23]}, {'label': 'Narain Karthikeyan', 'data': [24, 24, 23, 23, 24, 23, 23, None, None, None, None, None, None, None, None, 26, None, None]}, {'label': 'Daniel Ricciardo', 'data': [None, None, None, None, None, None, None, 26, 26, 26, 27, 27, 27, 27, 27, 27, 27, 27]}]