This option is available only for gauge charts. Use Quality Bands to break up a gauge into segments. Once you create these segments, you can add color to them.
For example, if you are using a gauge chart to track orders by region, you can add colored bands along the gauge to show that the red area of the gauge falls below the forecasted amount (for example, 0-499 orders), the yellow area of the gauge meets the forecasted amount (500-800 orders), and the green area of the gauge exceeds the forecasted amount (801-1000 orders).