The stock market appears to follow a 10-year cycle. During the first half of the decade equity prices on average do not increase, however in the second half they clearly do. In addition, during the 20th century U.S. equities have demonstrated very good performance in years ending with the number 5 (e.g. 1975, 1985 or 1995). Their average profit amounted to 34.61%. That equals half of the average profit for the entire decade! There were no losing years. On the other hand with years ending in 7 there were often price slumps.

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