A display system is provided that renders a horizontal situation indicator that includes required navigation performance (RNP) and estimated position uncertainty (EPU) values rendered non-numerically and in a fairly intuitive manner. A processor receives at least data representative of a desired course of the aircraft, data representative of the RNP for the aircraft, and data representative of the EPU for the aircraft. The processor renders, on a display device, a horizontal situation indicator that includes an aircraft symbol representative of a top-down view of the aircraft, an RNP boundary graphic representative of at least one RNP boundary for the aircraft, and an EPU graphic representative of the EPU for the aircraft. The aircraft symbol is rendered at a position that is representative of actual aircraft position relative to the desired course, and the RNP boundary graphic is rendered at a position relative to the rendered aircraft symbol and comprises a shaded region that shades a portion of the display device.