Question: what fraction of the british population was killed by the black death
[{'answer': '40 -- 60 %'}, {'provenance': [{'wikipedia_id': '20993417', 'title': 'Black Death in England', 'start_paragraph_id': 3, 'start_character': 0, 'end_paragraph_id': 3, 'end_character': 429, 'bleu_score': 0.8900892953072911, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 10718915467298503496}, 'section': 'Section::::Abstract.'}]}]