What is your actual net margin per Amazon SKU after all fees?

WITH revenue AS (
  SELECT
    i.sku,
    MAX(i.product_name)              AS product_name,
    SUM(i.item_price * i.quantity)   AS gross_revenue,
    SUM(i.quantity)                  AS units_sold
  FROM amazon_order_items i
  JOIN amazon_orders o ON o.amazon_order_id = i.amazon_order_id
  WHERE o.order_status NOT IN ('Canceled', 'Cancelled')
    AND i.item_price IS NOT NULL
    AND o.purchase_date::date >= CURRENT_DATE - INTERVAL '90 days'
  GROUP BY i.sku
),
fees AS (
  SELECT
    seller_sku                        AS sku,
    SUM(item_related_fee_amount)      AS total_fees
  FROM amazon_financial_events
  WHERE charge_type IN ('FBAPerUnitFulfillmentFee', 'Commission')
    AND posted_date::date >= CURRENT_DATE - INTERVAL '90 days'
  GROUP BY seller_sku
),
returns_cost AS (
  SELECT
    sku,
    COUNT(*) * AVG(f.estimated_referral_fee_per_unit) AS estimated_return_cost
  FROM amazon_returns r
  JOIN amazon_fba_fees f USING (sku)
  WHERE r.return_date::date >= CURRENT_DATE - INTERVAL '90 days'
  GROUP BY r.sku
)
SELECT
  r.sku,
  r.product_name,
  r.gross_revenue,
  COALESCE(f.total_fees, 0)          AS total_fees,
  COALESCE(rc.estimated_return_cost, 0) AS estimated_return_cost,
  r.gross_revenue
    - COALESCE(f.total_fees, 0)
    - COALESCE(rc.estimated_return_cost, 0) AS estimated_net,
  ROUND(
    (r.gross_revenue
      - COALESCE(f.total_fees, 0)
      - COALESCE(rc.estimated_return_cost, 0))
    / NULLIF(r.gross_revenue, 0) * 100, 2
  )                                   AS net_margin_pct
FROM revenue r
LEFT JOIN fees f USING (sku)
LEFT JOIN returns_cost rc USING (sku)
WHERE r.units_sold > 5
ORDER BY estimated_net DESC