The prediction interval defines the range above and below a predicted value where the value has some probability of occurring. For example, a prediction interval of 10% and 90% gives two points for each predicted value. The lower point represents the 10th percentile. The higher point represents the 90th percentile. The chance that the predicted value will fall within this range is 80%. The farther out the forecast is, the greater the size of this range.
To select a prediction interval, select from the Prediction interval list in the lower right corner of the Predictor Results window or select Custom to enter the wanted prediction interval in the Custom Prediction Interval dialog.