OPTIONS LINESIZE=80;
TITLE1 'n x m Latin Square Design';
TITLE2 'Response var. : Effect of catalyst on the';
TITLE3 '                reaction of a chemical process';
DATA CLOTH;
/* @@ means a loop in reading input variable sequence */
INPUT BOLT CHEMICAL STRENGTH @@;
CARDS;  
1 1 73   2 1 68   3 1 74   4 1 71   5 1 67 
1 2 73   2 2 67   3 2 75   4 2 72   5 2 70 
1 3 75   2 3 68   3 3 78   4 3 73   5 3 68 
1 4 73   2 4 71   3 4 75   4 4 75   5 4 69 
;
RUN;

/* Print the original data set                   */
PROC PRINT;
RUN;

/* Create Table & tabulate input data set        */
/* Nicety, but not absolutely necessary for      */
/* the analysis - you may skip                   */
PROC TABULATE;
     CLASS CHEMICAL BOLT ; 
     VAR STRENGTH;
     TABLE CHEMICAL, BOLT*STRENGTH; 
     KEYLABEL SUM='Y(IJ)'; 
RUN;

/* Analysis of Variance (ANOVA)                  */
PROC ANOVA;
     CLASS BOLT CHEMICAL;  
/* Dependent = Effects                           */
     MODEL  STRENGTH = BOLT CHEMICAL;
RUN;