Exemplary embodiments may compensate for loss of calibration by sensors that provide sensed analyte measurements to delivery devices. The exemplary embodiments may obtain one or more calibrated analyte measurements, such as by using techniques to obtain that the analyte measurement value that are known to produce properly calibrated analyte values. The one or more calibrated analyte measurements are compared to a recent analyte measurement to determine a negative or positive offset. The offset may be added to the recent analyte measurement to generate an updated analyte measurement that reflects the calibrated analyte measurement. In addition, past analyte measurement values within a time window may be updated as well by adding the offset to the past analyte measurement values. The exemplary embodiments may also compensate for the past over-delivery or under-delivery of an agent by the delivery device due to the loss of calibration.