Each of 21 impacts is broken into five sub-sections (each representing 2 2⁄3 of the circle) that classify the objective magnitude of the effect on a six-point scale (Likert, 1932), ranging from 0 for ‘‘no impact’’ to 5 for ‘‘extreme impact.’ Then, the binned magnitude and salience are plotted in green, with the radius of the circle representing the magnitude, while the arc of the circle represents the salience. Note that a different figure exist for a costs assessment and for a benefits assessment.  The sum of the shaded area for a completed IDAM characterization represents the aggregated costs and benefits.