Dilute-solution data on amplitude ratio and phase difference of stress and strain in sinusoidal shear testing are normally converted first to dynamic viscosity eta＇(c) and to eta "(c), where c is mass concentration of solute, and then extrapolated as c --> 0 to obtain the intrinsic values [eta＇] and [eta "]. The major source of error is usually measurement of phase angle, while amplitude ratio is more accurately determined. Here, it is shown that [eta＇] can be obtained from amplitude ratio alone, and also [eta "] from phase angle alone. Improved accuracy in obtaining [eta＇] is thereby possible with this new method of data analysis.