Question: when is the predetermined manufacturing overhead rate computed
[{'answer': 'before the period begins', 'provenance': [{'wikipedia_id': '2270140', 'title': 'Pre-determined overhead rate', 'start_paragraph_id': 1, 'start_character': 157, 'end_paragraph_id': 1, 'end_character': 181, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '2270140', 'title': 'Pre-determined overhead rate', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 695, 'bleu_score': 0.9437097370227521, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 8474355801265738995}, 'section': 'Section::::Abstract.'}]}]