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Forecast future periods

Turn on a forecast to project a time series past the edge of your data, with a confidence band and a horizon you choose - on a chart drawn on a Temporal axis.

3 min readUpdated November 2, 2026

A forecast projects a time series past the last date in your data. Golden fits the trend and any seasonality it can see in the history you already have, then draws the projection as a continuation of the same line or bars, with a shaded band showing how uncertain it is.

Turn on a forecast

  1. Build a chart with a date field on it, drawn on a Temporal (timeline) axis - forecasting is only offered on chart types that can draw past the data edge.
  2. Click Forecast in the toolbar above the chart. Its tooltip reads "Turn on forecast" the first time and "Forecast settings" afterwards.
  3. One click both turns the forecast on and opens its settings, so the projection appears immediately.
  4. Adjust Horizon and Band to taste - the chart redraws as you change them.
Note: Forecasting needs a timeline to project along. A chart whose date axis is set to Categorical, or built on a column that carries the "Treat dates as categories, not a timeline" setting, has no edge to project past, so Forecast is withheld - the toolbar explains with "Forecast needs a Temporal axis" or "Survey waves can't be forecast". Switch the chart's Axis Type back to Temporal, or clear that column setting, to forecast it.

The settings

  • Forecast - the on/off switch, described as "Project future periods from the trend".
  • Horizon - how far ahead to project. Auto, or 6, 12, or 24 periods.
  • Band - the confidence level of the shaded band: 80% (typical), 90%, or 95% (wide). It answers "How often the true value should land inside the shaded band".
Note: Longer horizons are sometimes grayed out. Period Overlay only ever draws one year ahead, so a horizon that would reach past that is disabled with a tooltip explaining why - the extra periods would not be drawn.

Reading the band

The single projected line is the middle of a range, not a promise. A wider band means the history was noisier, so treat the width as the real answer and the line as the midpoint of it. Widening the band from 80% to 95% does not make the forecast less certain - it draws more of the uncertainty that was always there.

Tip: Forecast settings live on the chart, and the same controls appear on dashboard chart cards, so a projection you set up in Analyze carries its settings when the chart is placed on a dashboard.