Revenue Retention Cohort Analysis - PostgreSQL

cohort.sql

-- Based on: https://medium.com/quick-code/how-to-write-sql-to-calculate-user-cohort-retention-a1b3b57c7a2f
-- Uses DATE_PART instead of DATE_DIFF as it is not supported by PostgreSQL

-- (branch_id, scheduled_for, total_cents)
WITH activities AS (
  SELECT branch_id, scheduled_for, total_cents
  FROM orders
  WHERE orders.status = 'complete'
),
-- (branch_id, cohort_month): cohort month is the first order date
cohort_items AS (
  SELECT branch_id, date_trunc('MONTH', MIN(scheduled_for))::DATE AS cohort_month
  FROM activities
  GROUP BY branch_id
  ORDER BY 1, 2
),
-- (branch_id, month_number, revenue): branch X has activity in month number X
branch_orders AS (
  SELECT A.branch_id, (DATE_PART('year', C.cohort_month) - DATE_PART('year', A.scheduled_for)) * 12 +
  (DATE_PART('month', C.cohort_month) - DATE_PART('month', A.scheduled_for)) AS month_number, SUM(A.total_cents) as revenue
  FROM activities A
  LEFT JOIN cohort_items C ON A.branch_id = C.branch_id
  GROUP BY 1, 2
  ORDER BY 1, 2
),
-- (cohort_month, count, revenue)
cohort_size AS (
  SELECT cohort_month, COUNT(DISTINCT A.branch_id) AS num_branches, SUM(A.total_cents) as revenue
  FROM cohort_items C
  LEFT JOIN activities A ON A.branch_id = C.branch_id
  GROUP BY 1
  ORDER BY 1
),
-- (cohort_month, month_number, count, revenue)
retention_table AS (
  SELECT C.cohort_month, A.month_number, COUNT(DISTINCT A.branch_id) AS num_branches, SUM(A.revenue) as revenue
  FROM branch_orders A
  LEFT JOIN cohort_items C ON A.branch_id = C.branch_id
  GROUP BY 1, 2
)
-- final value: (cohort_month, size, month_number, total_revenue, repeators, percentage)
SELECT B.cohort_month, S.num_branches AS total_branches, B.month_number, B.revenue / 100 as total_revenue, B.num_branches AS total_repeators, B.revenue / S.revenue as percentage
FROM retention_table B
LEFT JOIN cohort_size S ON B.cohort_month = S.cohort_month
WHERE B.cohort_month IS NOT NULL
ORDER BY 1, 3 desc

could you please provide the example dataset so that people can understand easily.
Thanks