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An analysis method is presented for determining the conventional cyclic material properties from uniaxial strain-life fatigue test data. The method focuses on improving fatigue life predictions for variable amplitude histories when a significant amount of damage is associated with small cycles. Under these conditions, it is necessary to extrapolate the strain-life curve below the constant amplitude endurance limit. This extrapolation requires careful attention to the curve fitting process to avoid the influence of endurance limit affected data. A fitting approach has been developed which identifies structure shifts in the data in order to obtain cyclic material properties not influenced by the endurance limit or other transitions that negatively impact life predictions.