A computer program product according to one embodiment includes a computer readable storage medium having program instructions embodied therewith. The program instructions are executable by a processing circuit to cause the circuitry to perform a method including determining, after writing data to a non-volatile memory block, one or more delta threshold voltage shift (TVSΔ) values. One or more overall threshold voltage shift values for the data written to the non-volatile memory block are calculated, the values being a function of the one or more TVSΔ values to be used when writing data to the non-volatile memory block. The overall threshold voltage shift values are stored. A base threshold voltage shift (TVSBASE) value, the one or more TVSΔ values, or both the TVSBASE value and the one or more TVSΔ values are re-calibrated during a background health check after a predetermined number of background health checks without calibration are performed.