sample 21 c2 c3			#takes from C2, randomizes, stores in C3
unstack c1 c4 c5; 		#separates the values in C1 into 2
subs c3;	 		#columns using the group assigned in C3
varnames.			#uses the category names as column name
let c6(k1)=mean(c4)-mean(c5)
let k1=k1+1			#an integer counter that keeps track of which row the