Many ASTM standards (for example, ASTM E8, Standard Test Methods for Tension Testing of Metallic Materials; ASTM E9, Standard Test Methods of Compression Testing of Metallic Materials at Room Temperature; and ASTM E111, Standard Test Method for Young's Modulus, Tangent Modulus, and Chord Modulus) require slope determination as part of data analysis but do not specify an objective method for making this determination. This lack of method leads to increased variability, which impacts precision and bias. In 2007, work began to develop an algorithm that would perform an objective determination of slope. That algorithm became known as SDAR (Slope Determination by Analysis of Residuals). In 2011, ASTM Committee E08 on Fatigue and Fracture began developing a draft standard practice based on the SDAR algorithm. Because implementation of the algorithm is computationally intensive, there were concerns about its complexities. The ability of users to code the algorithm in the language or application of their choice was evaluated by way of two analytical round robins. The results of those two round robins are here presented and the conclusions derived from them are discussed.