A graphical indicator to assist a user in adjusting the value of a parameter to a target value. The graphical indicator has target value indicia that represents a target value of the parameter, and measured value indicia that represents a measured value of the parameter. A change in a measured value of the parameter relative to the target value is represented by a first corresponding amount of movement of the measured value indicia relative to the target value indicia when the measured value is within a first span of parameter values, and a second, different corresponding amount of movement of the measured value indicia relative to the target value indicia when the measured value is within a second span of parameter values. The graphical indicator provides increased sensitivity to changes in the measured value of the parameter as the measured value becomes closer to the target value of the parameter.