How the forecast works. Revenue is split into a seasonal shape and an annual level: forecast(period) = annual level × seasonal share(period) The seasonal share is each period's average % of its year's total — it works from a single year and is shrunk toward an even split when history is thin (no noisy month-on-month ratios). The annual level blends a history expectation — prev-year total × damped growth — with a run-rate annualisation of the periods already entered this year (entered ÷ seasonal weight covered); the more of the year that's filled in, the more the actuals steer it. Best / Worst apply ±1 standard deviation of historical growth. The projected Total = entered actuals + forecast periods. Only one year of data? It repeats that year's seasonal shape at a damped growth rate with a wider band.