The offset yield strength is reported as a stress (psi, MPa, etc) and is defined as the point where a line drawn parallel to the modulus line intersects the stress-strain curve (see point B and line XB ).
Offset distance, 0X, in Figure 1 is the product of sample gauge length and percent offset. Offset distance, 0X, for example would be 0.004 in for a 2 in gage length sample at 0.2% offset (0X = 2 in x 0.002 = 0.004 in).