A method for controlling a power system control area according to a first and a second control performance standard, wherein operation of the control area determines area control parameter values. The method comprises (a) determining a first compliance target for the first performance standard and a second compliance target for the second performance standard (100/200); (b) determining a first performance standard statistical measure responsive to the control area parameter values from a beginning of a first compliance period to a time at which the first average is determined (108); (c) determining a second performance standard statistical measure responsive to the control area parameter values from a beginning of a second compliance period to a time at which the second average is determined; (d) determining a first area control parameter target responsive to the first performance standard statistical measure (116); (e) determining a second area control parameter target responsive to the second performance standard statistical measure (204); (f) determining a first area control parameter correction responsive to the first area control parameter target and the area control parameter values (150); (g) determining a second area control parameter correction responsive to the second area control parameter target and the area control parameter values (228) and (h) controlling the power system according to one or both of the first and the second area control parameter corrections (154/232).