def sum_period_review_request_stats(raw_aggregation):
    """Compute statistics from aggregated review request data for one aggregation point."""
    state_dict, late_state_dict, result_dict, assignment_to_closure_days_list, assignment_to_closure_days_count = raw_aggregation

    res = {}
    res["state"] = state_dict
    res["result"] = result_dict

    res["open"] = sum(state_dict.get(s, 0) for s in ("requested", "accepted"))
    res["completed"] = sum(state_dict.get(s, 0) for s in ("completed", "part-completed"))
    res["not_completed"] = sum(state_dict.get(s, 0) for s in state_dict if s in ("rejected", "withdrawn", "overtaken", "no-response"))

    res["open_late"] = sum(late_state_dict.get(s, 0) for s in ("requested", "accepted"))
    res["open_in_time"] = res["open"] - res["open_late"]
    res["completed_late"] = sum(late_state_dict.get(s, 0) for s in ("completed", "part-completed"))
    res["completed_in_time"] = res["completed"] - res["completed_late"]

    res["average_assignment_to_closure_days"] = float(sum(assignment_to_closure_days_list)) / (assignment_to_closure_days_count or 1) if assignment_to_closure_days_list else None

    return res