1967 



20 



19 

 -18 



17 

 hl6 



15 

 -14 

 -13 



12 



11 



10 



9 

 h8 



7 



6 

 -5 

 -4 

 -3 

 -2 



1 



' I" 'I' "I" ■ I" 'I " 'I" 'I" 'I'" r " I" '1" 'I' ' 'I " T "I" 'I " 'I'l 'I " ' I' 'M' 



SALES J FMAMJ J ASONDJ FMAMJ J ASOND 



PRICE 



COST 



3 



o 



Q. 



c 



3 



E 



O 

 CO 



1968 



Appendix Figure 4. — Frozen ocean perch fillets — weekly retail prices, purchase costs, and sales volume from a Chicago food cha 



store with 20 branches, 1967 and 1968. 



27 



