The anticipated operational performance for future conditions considers a sensitivity testing-approach that varies the design year peak period traffic volumes by more or less an assigned percentage (i.e., +/- 30 percent).

This accounts for the uncertainty of future traffic conditions, especially at intersections where a roundabout is installed with adjacent land use that is undeveloped or anticipated to re-develop before the design year. Sensitivity testing may reveal that the chosen entry or a specific lane would experience excessive queuing. Varying the mode to be used for analysis and varying the geometry or lane configuration are also useful sensitivity testing considerations. Often the most probable result is not the exact result produced by any given model, but with a range of results produced by more than one type of model or for more than one geometry.