Every figure in DueWise can be reproduced by hand.

balance = invoice.amount − Σ completed payments
status  = paid            if balance ≤ 0.005
          partially_paid  if payments > 0
          overdue         if due_date < today (display)

Drafts are excluded from receivables. Pending or failed payments never reduce a balance.

days_overdue = max(0, today − due_date)
bucket = Current | 1–30 | 31–60 | 60+

Ageing uses remaining balances, so partial payments reduce the amount in each bucket.

delay        = settlement_date − due_date   (per fully paid invoice)
on_time_rate = count(delay ≤ 0) / n
median_delay = max(0, median(delay))
sufficient   = n ≥ 3

Settlement date is the date of the payment that completed the invoice.

p = 0.40 + 0.55 × on_time_rate   if sufficient
p = 0.75                         otherwise
p × 0.85 if 1–30 days overdue
p × 0.70 if 31–60 days overdue
p × 0.50 if 60+ days overdue
p clamped to [0.20, 0.95]

Customers with fewer than 3 settled invoices are shown as lower-confidence estimates.

scheduled     = balance on due_date (overdue → today)
expected_date = max(today, due_date + median_delay)
expected      = balance × p   if expected_date ≤ horizon
at_risk       = scheduled − expected

7- and 30-day views use daily buckets; the 90-day view uses weekly buckets.

low_share  = scheduled from customers without sufficient history / scheduled
confidence = min(90, 35 + 45 × (1 − low_share) + min(10, completed_payments))

Labelled “Lower-confidence estimate” when low_share > 50%.

High   if days_overdue > 30, or overdue with balance ≥ $5,000
Medium if overdue, or balance ≥ $10,000
Normal otherwise
sort: priority → days_overdue → balance

Every worklist item shows the rule that placed it.