Marty Zweig detailed what became known as the Zweig Breadth Thrust buy signal in his book, Winning on Wall Street, which was first published in 1986. A ZBT buy signal is generated when NYSE breadth moves from an oversold extreme to an overbought extreme within 10 trading days. ZBT signals are very rare. The book described 14 signals since 1945. The average gain following these 14 Thrusts was 24.6% within 11 months.
The market surge in late May just missed generating a ZBT. The market achieved the breadth thrust in 11 days, not 10. Since then, a number of chartists have analyzed these "just missed" signals and concluded that they are nearly just as good as the classic ZBT buy signal. As an example, Recession Alert observed:All but 2 of the 13 signals in the above chart provided positive gains averaging 8.4% some 6 month out, which is equivalent to a 84.6% accuracy. If you relaxed the positive outcome holding period from 6 months to 12 months, then only the 2001 signal provided a negative outcome, increasing the accuracy to 92%. In fact, an examination of an actuarial table of the SP-500 gains for various holding periods after each ZBT-A signal yields some more interesting results.
Does that mean it's time to sound the all-clear and buy stocks?
The full post can be found here.
