A storage system includes a charge storage cell and a controller. The charge storage cell includes first and second charge storage regions, each capable of assuming a plurality of charge levels. The controller programs the first charge storage region to one of the plurality of charge levels and then programs the second charge storage region to one of the plurality of charge levels. The controller reads a charge level stored in the first charge storage region based upon a first measurement of the first charge storage region and a second measurement of the second charge storage region.