New sheet before the active one with the sorted history, a FORECAST.ETS
forecast column, FORECAST.ETS.CONFINT lower/upper bounds, an optional
FORECAST.ETS.STAT table, an Excel table over the data and a line or column
chart. Parameters: timeline/values (default: the selection's first two
columns), end or periods, confidence interval, seasonality, missing-point
fill, duplicate aggregation, statistics, chart kind. Data ribbon button
opens a form dialog; programmatic calls never do. gridcraft-functions
exports Timeline to continue a timeline (numeric step or calendar months).
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
AAA exponential smoothing (Hyndman et al. 2008, ETS(A,A,A)) over an evenly
spaced timeline: documented seasonality, data completion and aggregation
arguments, calendar-month date timelines, autocorrelation seasonality
detection, state-space prediction intervals, statistic types 1-8.
Smoothing parameters minimise the in-sample SSE (grid + clamped
Nelder-Mead). XLSX export treats the family's range arguments as
array-taking (no spurious dynamic-array metadata), FORECAST/FORECAST.LINEAR
included.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
