usage monitor 320 in accordance with an embodiment of the present invention when a monitoring cycle commences monitor 320 begins to monitor usage of device 200 starting with the first of a plurality of periods and continuing for each successive period within the cycle 410 a monitoring cycle may commence when the current time from clock 250 conforms to a monitoring cycle start time programmed in monitor 320 in other embodiments monitoring may be continuously performed a period within a monitoring cycle is a block of time for example an hour within a one day cycle clock 250 may be referenced to determine the current period within the cycle continuing with fig4 when usage monitor 320 detects an in use event a use value maintained for the current period is incremented and a timer is started 420 if device 200 is still in use when the timer expires 430 the use value is again incremented and the timer is restarted if however device 200 is no longer in use when the timer expires usage monitor 320 monitors for a new in use event 410 it will be appreciated that by incrementing and setting a timer in loop for as long as device 200 remains in use a more precise usage profile may be obtained for example if a one minute timer is employed in a cycle having a multiple of one hour periods over the cycle the use value for each period will be incremented between zero and 60 times rather than zero or one time as would occur in the absence of a timer continuing further with fig4 when the lost period ends use values for each period are normalized 440 for each period a normalized.