76 



Economic Cycles: Their Law and Cause 





<-30 



5: 





-a? 



c 



IS 



-45 



-Z5 



y = 



-IO *-5 +ZO + 35 *SO + 65 



Percentage change in the production of potatoes. 



Figure 20. The law of demand for potatoes. 

 1.77 — 1.5062X 4- .02489x2— .000197a; 3 , origin at (0, 0). 



