The present disclosure provides systems for predicting semiconductor reliability. In an embodiment a method for predicting the semiconductor reliability includes receiving a degradation parameter input of a semiconductor device and using a degradation equation to determine a plurality of bias dependent slope values for degradation over a short time period according to the degradation parameter input. The plurality of slope values include at least two different slope values for degradation over time. The system accumulates the plurality of slope values and projects the accumulated slope values over a long time period to determine a stress effect for the semiconductor device.