Origin of Eight-Year Generating Cycle 



73 



ACTUAL Index NUMKM Of PRICE5 



ToRecAST iNDtx NuM6tRS OF Prices 



generatin8 cycles of yield per acre 

 Derived Cycles of prices 



Figure 19 

 Upper part: Actual index numbers of prices of the six representative crops and the 

 index numbers of prices forecast from the index numbers of the yield 

 per acre by means of the formula 



V = - 1.295x - .02. 

 Lower part: Generating cycles of the yield per acre of the crops, 

 J/ = 1.6 + 20.0 sin (45°< + 109°), origin at 1SS2; 

 Derived cycles of prices of the crops compute 1 from the generating cycles 

 of yield by means of the formula, 



y = — 1.295j; - .02. 



val should reveal the existence of the eight-year generat- 

 ing cycle of crops. Moreover, if the generating cycle is 

 a persistent, real cycle, then the cycle of yield per acre 

 that is revealed indirectly by the record of prices 

 throughout a long interval should be the same as the 

 cycle that is obtained directly from the more recent 



