Cotton prices in the United States are available by crop years from 1731-32. These prices have fluctuated, over the entire time span covered by the investigation, in rhythmic cycles; the average period of one of these is 5.9 yrs. The 5.9-yr cycle in this series of figures has high statistical significance. Other significant cycles are also present in this series. Buying and selling on the basis of this 5.9-yr cycle would have been profitable. Cycles with periods of 5.9 yrs are well-established in many natural and social science phenomena. Phases of all 5.9-yr cycles, regardless of discipline, tend to cluster. The detailed characteristics of the 5.9-yr cycle in the Cotton Price Index are as follow: Span of Time: 234 yrs (nearly 40 repetitions); Period: Mean period: 5.9 yrs; Phase: An idealized crest comes currently at 1970.9; Wave Form: On the average, the waves are triangular in shape, and symmetrical around both X and Y axes; Strength: On the average, the amplitude of the cycle is 7.8% of trend (A 5-yr moving average trend was used.); Regularity: A majority of the crests and troughs of this wave in the detrended Index falls within a year one way or the other from ideal timing; Significance: In the detrended data, this cycle would not have occurred by chance more than once in 1,000 times.
Journal description