The OUTPUT statement creates the TESTSTAT data set with nine variables. MEAN= saves the mean for Test1 and Test2. STD= saves the standard deviation for Test1. PCTLPTS= calculates three percentiles and PCTLPRE= specifies prefix names for the analysis variables. PCTLNAME= specifies a suffix name for the 33.3 percentile. 
   output out=teststat mean=MeanTest1 MeanTest2 
          std=StdDeviationTest1
          pctlpts=33.3 66 99.9
          pctlpre=Test1_ 
          Test2_ pctlname=Low ;
run;