If your data consists of (x,y) pairs, you can calculate the area under a curve by using the EXPAND procedure in SAS/ETS^® software. The sample program SAS Note 24990 illustrates how to use PROC EXPAND to calculate the area under the curve using either the trapezoid rule or a cubic spline to approximate the function.

For the particular case of computing the area under the ROC (receiver characteristic operating) curve, see "ROC (Receiver Operating Characteristic) curve" in SAS Note 30333.