FORECASTS

Forecasting models extrapolate future values of a time series based on its historical values, allowing you to attempt to predict the evolution of a measure. Many different mathematical models can be used for such endeavors, each with its own advantages and drawbacks. Tableau's forecasting tool uses what is called exponential smoothing.

In such models, more recent data points are assigned greater weights than older observations. They work reasonably well to capture both long‐term trends and any potential seasonality that may be present in the time series. The resulting forecast is shown directly in the chart.

Because we are talking about time‐series data, ensure that your view contains a time or date field as well as a measure.

Adding a Forecast Line to the View

To illustrate the process, let's try to predict sales revenue for the next year using the Superstore dataset.

Create a line chart, with Sales on Rows and Order Date (as continuous months) on Columns...