data stocks; Y = 100; Z=100; 
 do t = 1 to 250; * 900 ; 
   e = normal(8276531); 
   Y=Y+e; Z = 100 + .90*(Z-100) + e; 
   output; end; 
proc gplot; plot (Y Z)*t / overlay; 
Title c=blue "Closing Prices, stocks " c=black "Y " c=blue "and " c=red "Z";
symbol1 v=none i=join w=2; 
proc arima; i var=Y nlag=10 stationarity=(adf); 
i var=Z nlag=10 stationarity=(adf);
run;