How the forecast works: for every paid invoice we compute days_to_pay = payment_date − invoice_date. The median becomes each client's expected delay; p25 and p75 form a 50% confidence band. Open invoices land in the chart at invoice_date + median_days, with the band showing how early (p25) or late (p75) they might actually pay. Clients with fewer than 3 paid invoices use the firm-wide baseline of — median. Visit any client page to inspect their behavior in detail.